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1This is libgomp.info, produced by makeinfo version 4.12 from
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3
4Copyright (C) 2006-2013 Free Software Foundation, Inc.
5
6   Permission is granted to copy, distribute and/or modify this document
7under the terms of the GNU Free Documentation License, Version 1.3 or
8any later version published by the Free Software Foundation; with the
9Invariant Sections being "Funding Free Software", the Front-Cover texts
10being (a) (see below), and with the Back-Cover Texts being (b) (see
11below).  A copy of the license is included in the section entitled "GNU
12Free Documentation License".
13
14   (a) The FSF's Front-Cover Text is:
15
16   A GNU Manual
17
18   (b) The FSF's Back-Cover Text is:
19
20   You have freedom to copy and modify this GNU Manual, like GNU
21software.  Copies published by the Free Software Foundation raise
22funds for GNU development.
23
24INFO-DIR-SECTION GNU Libraries
25START-INFO-DIR-ENTRY
26* libgomp: (libgomp).                    GNU OpenMP runtime library
27END-INFO-DIR-ENTRY
28
29   This manual documents the GNU implementation of the OpenMP API for
30multi-platform shared-memory parallel programming in C/C++ and Fortran.
31
32   Published by the Free Software Foundation 51 Franklin Street, Fifth
33Floor Boston, MA 02110-1301 USA
34
35   Copyright (C) 2006-2013 Free Software Foundation, Inc.
36
37   Permission is granted to copy, distribute and/or modify this document
38under the terms of the GNU Free Documentation License, Version 1.3 or
39any later version published by the Free Software Foundation; with the
40Invariant Sections being "Funding Free Software", the Front-Cover texts
41being (a) (see below), and with the Back-Cover Texts being (b) (see
42below).  A copy of the license is included in the section entitled "GNU
43Free Documentation License".
44
45   (a) The FSF's Front-Cover Text is:
46
47   A GNU Manual
48
49   (b) The FSF's Back-Cover Text is:
50
51   You have freedom to copy and modify this GNU Manual, like GNU
52software.  Copies published by the Free Software Foundation raise
53funds for GNU development.
54
55
56File: libgomp.info,  Node: Top,  Next: Enabling OpenMP,  Up: (dir)
57
58Introduction
59************
60
61This manual documents the usage of libgomp, the GNU implementation of
62the OpenMP (http://www.openmp.org) Application Programming Interface
63(API) for multi-platform shared-memory parallel programming in C/C++
64and Fortran.
65
66* Menu:
67
68* Enabling OpenMP::            How to enable OpenMP for your applications.
69* Runtime Library Routines::   The OpenMP runtime application programming
70                               interface.
71* Environment Variables::      Influencing runtime behavior with environment
72                               variables.
73* The libgomp ABI::            Notes on the external ABI presented by libgomp.
74* Reporting Bugs::             How to report bugs in GNU OpenMP.
75* Copying::                    GNU general public license says
76                               how you can copy and share libgomp.
77* GNU Free Documentation License::
78                               How you can copy and share this manual.
79* Funding::                    How to help assure continued work for free
80                               software.
81* Library Index::              Index of this documentation.
82
83
84File: libgomp.info,  Node: Enabling OpenMP,  Next: Runtime Library Routines,  Prev: Top,  Up: Top
85
861 Enabling OpenMP
87*****************
88
89To activate the OpenMP extensions for C/C++ and Fortran, the
90compile-time flag `-fopenmp' must be specified. This enables the OpenMP
91directive `#pragma omp' in C/C++ and `!$omp' directives in free form,
92`c$omp', `*$omp' and `!$omp' directives in fixed form, `!$' conditional
93compilation sentinels in free form and `c$', `*$' and `!$' sentinels in
94fixed form, for Fortran. The flag also arranges for automatic linking
95of the OpenMP runtime library (*note Runtime Library Routines::).
96
97   A complete description of all OpenMP directives accepted may be
98found in the OpenMP Application Program Interface
99(http://www.openmp.org) manual, version 3.1.
100
101
102File: libgomp.info,  Node: Runtime Library Routines,  Next: Environment Variables,  Prev: Enabling OpenMP,  Up: Top
103
1042 Runtime Library Routines
105**************************
106
107The runtime routines described here are defined by section 3 of the
108OpenMP specifications in version 3.1. The routines are structured in
109following three parts:
110
111   Control threads, processors and the parallel environment.
112
113* Menu:
114
115* omp_get_active_level::        Number of active parallel regions
116* omp_get_ancestor_thread_num:: Ancestor thread ID
117* omp_get_dynamic::             Dynamic teams setting
118* omp_get_level::               Number of parallel regions
119* omp_get_max_active_levels::   Maximum number of active regions
120* omp_get_max_threads::         Maximum number of threads of parallel region
121* omp_get_nested::              Nested parallel regions
122* omp_get_num_procs::           Number of processors online
123* omp_get_num_threads::         Size of the active team
124* omp_get_schedule::            Obtain the runtime scheduling method
125* omp_get_team_size::           Number of threads in a team
126* omp_get_thread_limit::        Maximum number of threads
127* omp_get_thread_num::          Current thread ID
128* omp_in_parallel::             Whether a parallel region is active
129* omp_in_final::                Whether in final or included task region
130* omp_set_dynamic::             Enable/disable dynamic teams
131* omp_set_max_active_levels::   Limits the number of active parallel regions
132* omp_set_nested::              Enable/disable nested parallel regions
133* omp_set_num_threads::         Set upper team size limit
134* omp_set_schedule::            Set the runtime scheduling method
135
136   Initialize, set, test, unset and destroy simple and nested locks.
137
138* Menu:
139
140* omp_init_lock::            Initialize simple lock
141* omp_set_lock::             Wait for and set simple lock
142* omp_test_lock::            Test and set simple lock if available
143* omp_unset_lock::           Unset simple lock
144* omp_destroy_lock::         Destroy simple lock
145* omp_init_nest_lock::       Initialize nested lock
146* omp_set_nest_lock::        Wait for and set simple lock
147* omp_test_nest_lock::       Test and set nested lock if available
148* omp_unset_nest_lock::      Unset nested lock
149* omp_destroy_nest_lock::    Destroy nested lock
150
151   Portable, thread-based, wall clock timer.
152
153* Menu:
154
155* omp_get_wtick::            Get timer precision.
156* omp_get_wtime::            Elapsed wall clock time.
157
158
159File: libgomp.info,  Node: omp_get_active_level,  Next: omp_get_ancestor_thread_num,  Up: Runtime Library Routines
160
1612.1 `omp_get_active_level' - Number of parallel regions
162=======================================================
163
164_Description_:
165     This function returns the nesting level for the active parallel
166     blocks, which enclose the calling call.
167
168_C/C++_
169     _Prototype_:  `int omp_get_active_level(void);'
170
171_Fortran_:
172     _Interface_:  `integer function omp_get_active_level()'
173
174_See also_:
175     *note omp_get_level::, *note omp_get_max_active_levels::, *note
176     omp_set_max_active_levels::
177
178_Reference_:
179     OpenMP specifications v3.1 (http://www.openmp.org/), section
180     3.2.19.
181
182
183File: libgomp.info,  Node: omp_get_ancestor_thread_num,  Next: omp_get_dynamic,  Prev: omp_get_active_level,  Up: Runtime Library Routines
184
1852.2 `omp_get_ancestor_thread_num' - Ancestor thread ID
186======================================================
187
188_Description_:
189     This function returns the thread identification number for the
190     given nesting level of the current thread. For values of LEVEL
191     outside zero to `omp_get_level' -1 is returned; if LEVEL is
192     `omp_get_level' the result is identical to `omp_get_thread_num'.
193
194_C/C++_
195     _Prototype_:  `int omp_get_ancestor_thread_num(int level);'
196
197_Fortran_:
198     _Interface_:  `integer function omp_get_ancestor_thread_num(level)'
199                   `integer level'
200
201_See also_:
202     *note omp_get_level::, *note omp_get_thread_num::, *note
203     omp_get_team_size::
204
205_Reference_:
206     OpenMP specifications v3.1 (http://www.openmp.org/), section
207     3.2.17.
208
209
210File: libgomp.info,  Node: omp_get_dynamic,  Next: omp_get_level,  Prev: omp_get_ancestor_thread_num,  Up: Runtime Library Routines
211
2122.3 `omp_get_dynamic' - Dynamic teams setting
213=============================================
214
215_Description_:
216     This function returns `true' if enabled, `false' otherwise.  Here,
217     `true' and `false' represent their language-specific counterparts.
218
219     The dynamic team setting may be initialized at startup by the
220     `OMP_DYNAMIC' environment variable or at runtime using
221     `omp_set_dynamic'. If undefined, dynamic adjustment is disabled by
222     default.
223
224_C/C++_:
225     _Prototype_:  `int omp_get_dynamic(void);'
226
227_Fortran_:
228     _Interface_:  `logical function omp_get_dynamic()'
229
230_See also_:
231     *note omp_set_dynamic::, *note OMP_DYNAMIC::
232
233_Reference_:
234     OpenMP specifications v3.1 (http://www.openmp.org/), section 3.2.8.
235
236
237File: libgomp.info,  Node: omp_get_level,  Next: omp_get_max_active_levels,  Prev: omp_get_dynamic,  Up: Runtime Library Routines
238
2392.4 `omp_get_level' - Obtain the current nesting level
240======================================================
241
242_Description_:
243     This function returns the nesting level for the parallel blocks,
244     which enclose the calling call.
245
246_C/C++_
247     _Prototype_:  `int omp_get_level(void);'
248
249_Fortran_:
250     _Interface_:  `integer function omp_level()'
251
252_See also_:
253     *note omp_get_active_level::
254
255_Reference_:
256     OpenMP specifications v3.1 (http://www.openmp.org/), section
257     3.2.16.
258
259
260File: libgomp.info,  Node: omp_get_max_active_levels,  Next: omp_get_max_threads,  Prev: omp_get_level,  Up: Runtime Library Routines
261
2622.5 `omp_get_max_active_levels' - Maximum number of active regions
263==================================================================
264
265_Description_:
266     This function obtains the maximum allowed number of nested, active
267     parallel regions.
268
269_C/C++_
270     _Prototype_:  `int omp_get_max_active_levels(void);'
271
272_Fortran_:
273     _Interface_:  `integer function omp_get_max_active_levels()'
274
275_See also_:
276     *note omp_set_max_active_levels::, *note omp_get_active_level::
277
278_Reference_:
279     OpenMP specifications v3.1 (http://www.openmp.org/), section
280     3.2.15.
281
282
283File: libgomp.info,  Node: omp_get_max_threads,  Next: omp_get_nested,  Prev: omp_get_max_active_levels,  Up: Runtime Library Routines
284
2852.6 `omp_get_max_threads' - Maximum number of threads of parallel region
286========================================================================
287
288_Description_:
289     Return the maximum number of threads used for the current parallel
290     region that does not use the clause `num_threads'.
291
292_C/C++_:
293     _Prototype_:  `int omp_get_max_threads(void);'
294
295_Fortran_:
296     _Interface_:  `integer function omp_get_max_threads()'
297
298_See also_:
299     *note omp_set_num_threads::, *note omp_set_dynamic::, *note
300     omp_get_thread_limit::
301
302_Reference_:
303     OpenMP specifications v3.1 (http://www.openmp.org/), section 3.2.3.
304
305
306File: libgomp.info,  Node: omp_get_nested,  Next: omp_get_num_procs,  Prev: omp_get_max_threads,  Up: Runtime Library Routines
307
3082.7 `omp_get_nested' - Nested parallel regions
309==============================================
310
311_Description_:
312     This function returns `true' if nested parallel regions are
313     enabled, `false' otherwise. Here, `true' and `false' represent
314     their language-specific counterparts.
315
316     Nested parallel regions may be initialized at startup by the
317     `OMP_NESTED' environment variable or at runtime using
318     `omp_set_nested'. If undefined, nested parallel regions are
319     disabled by default.
320
321_C/C++_:
322     _Prototype_:  `int omp_get_nested(void);'
323
324_Fortran_:
325     _Interface_:  `logical function omp_get_nested()'
326
327_See also_:
328     *note omp_set_nested::, *note OMP_NESTED::
329
330_Reference_:
331     OpenMP specifications v3.1 (http://www.openmp.org/), section
332     3.2.10.
333
334
335File: libgomp.info,  Node: omp_get_num_procs,  Next: omp_get_num_threads,  Prev: omp_get_nested,  Up: Runtime Library Routines
336
3372.8 `omp_get_num_procs' - Number of processors online
338=====================================================
339
340_Description_:
341     Returns the number of processors online.
342
343_C/C++_:
344     _Prototype_:  `int omp_get_num_procs(void);'
345
346_Fortran_:
347     _Interface_:  `integer function omp_get_num_procs()'
348
349_Reference_:
350     OpenMP specifications v3.1 (http://www.openmp.org/), section 3.2.5.
351
352
353File: libgomp.info,  Node: omp_get_num_threads,  Next: omp_get_schedule,  Prev: omp_get_num_procs,  Up: Runtime Library Routines
354
3552.9 `omp_get_num_threads' - Size of the active team
356===================================================
357
358_Description_:
359     Returns the number of threads in the current team. In a sequential
360     section of the program `omp_get_num_threads' returns 1.
361
362     The default team size may be initialized at startup by the
363     `OMP_NUM_THREADS' environment variable. At runtime, the size of
364     the current team may be set either by the `NUM_THREADS' clause or
365     by `omp_set_num_threads'. If none of the above were used to define
366     a specific value and `OMP_DYNAMIC' is disabled, one thread per CPU
367     online is used.
368
369_C/C++_:
370     _Prototype_:  `int omp_get_num_threads(void);'
371
372_Fortran_:
373     _Interface_:  `integer function omp_get_num_threads()'
374
375_See also_:
376     *note omp_get_max_threads::, *note omp_set_num_threads::, *note
377     OMP_NUM_THREADS::
378
379_Reference_:
380     OpenMP specifications v3.1 (http://www.openmp.org/), section 3.2.2.
381
382
383File: libgomp.info,  Node: omp_get_schedule,  Next: omp_get_team_size,  Prev: omp_get_num_threads,  Up: Runtime Library Routines
384
3852.10 `omp_get_schedule' - Obtain the runtime scheduling method
386==============================================================
387
388_Description_:
389     Obtain the runtime scheduling method. The KIND argument will be
390     set to the value `omp_sched_static', `omp_sched_dynamic',
391     `omp_sched_guided' or `omp_sched_auto'. The second argument,
392     MODIFIER, is set to the chunk size.
393
394_C/C++_
395     _Prototype_:  `void omp_schedule(omp_sched_t *kind, int *modifier);'
396
397_Fortran_:
398     _Interface_:  `subroutine omp_schedule(kind, modifier)'
399                   `integer(kind=omp_sched_kind) kind'
400                   `integer modifier'
401
402_See also_:
403     *note omp_set_schedule::, *note OMP_SCHEDULE::
404
405_Reference_:
406     OpenMP specifications v3.1 (http://www.openmp.org/), section
407     3.2.12.
408
409
410File: libgomp.info,  Node: omp_get_team_size,  Next: omp_get_thread_limit,  Prev: omp_get_schedule,  Up: Runtime Library Routines
411
4122.11 `omp_get_team_size' - Number of threads in a team
413======================================================
414
415_Description_:
416     This function returns the number of threads in a thread team to
417     which either the current thread or its ancestor belongs. For
418     values of LEVEL outside zero to `omp_get_level', -1 is returned;
419     if LEVEL is zero, 1 is returned, and for `omp_get_level', the
420     result is identical to `omp_get_num_threads'.
421
422_C/C++_:
423     _Prototype_:  `int omp_get_team_size(int level);'
424
425_Fortran_:
426     _Interface_:  `integer function omp_get_team_size(level)'
427                   `integer level'
428
429_See also_:
430     *note omp_get_num_threads::, *note omp_get_level::, *note
431     omp_get_ancestor_thread_num::
432
433_Reference_:
434     OpenMP specifications v3.1 (http://www.openmp.org/), section
435     3.2.18.
436
437
438File: libgomp.info,  Node: omp_get_thread_limit,  Next: omp_get_thread_num,  Prev: omp_get_team_size,  Up: Runtime Library Routines
439
4402.12 `omp_get_thread_limit' - Maximum number of threads
441=======================================================
442
443_Description_:
444     Return the maximum number of threads of the program.
445
446_C/C++_:
447     _Prototype_:  `int omp_get_thread_limit(void);'
448
449_Fortran_:
450     _Interface_:  `integer function omp_get_thread_limit()'
451
452_See also_:
453     *note omp_get_max_threads::, *note OMP_THREAD_LIMIT::
454
455_Reference_:
456     OpenMP specifications v3.1 (http://www.openmp.org/), section
457     3.2.13.
458
459
460File: libgomp.info,  Node: omp_get_thread_num,  Next: omp_in_parallel,  Prev: omp_get_thread_limit,  Up: Runtime Library Routines
461
4622.13 `omp_get_thread_num' - Current thread ID
463=============================================
464
465_Description_:
466     Returns a unique thread identification number within the current
467     team.  In a sequential parts of the program, `omp_get_thread_num'
468     always returns 0. In parallel regions the return value varies from
469     0 to `omp_get_num_threads'-1 inclusive. The return value of the
470     master thread of a team is always 0.
471
472_C/C++_:
473     _Prototype_:  `int omp_get_thread_num(void);'
474
475_Fortran_:
476     _Interface_:  `integer function omp_get_thread_num()'
477
478_See also_:
479     *note omp_get_num_threads::, *note omp_get_ancestor_thread_num::
480
481_Reference_:
482     OpenMP specifications v3.1 (http://www.openmp.org/), section 3.2.4.
483
484
485File: libgomp.info,  Node: omp_in_parallel,  Next: omp_in_final,  Prev: omp_get_thread_num,  Up: Runtime Library Routines
486
4872.14 `omp_in_parallel' - Whether a parallel region is active
488============================================================
489
490_Description_:
491     This function returns `true' if currently running in parallel,
492     `false' otherwise. Here, `true' and `false' represent their
493     language-specific counterparts.
494
495_C/C++_:
496     _Prototype_:  `int omp_in_parallel(void);'
497
498_Fortran_:
499     _Interface_:  `logical function omp_in_parallel()'
500
501_Reference_:
502     OpenMP specifications v3.1 (http://www.openmp.org/), section 3.2.6.
503
504
505File: libgomp.info,  Node: omp_in_final,  Next: omp_set_dynamic,  Prev: omp_in_parallel,  Up: Runtime Library Routines
506
5072.15 `omp_in_final' - Whether in final or included task region
508==============================================================
509
510_Description_:
511     This function returns `true' if currently running in a final or
512     included task region, `false' otherwise. Here, `true' and `false'
513     represent their language-specific counterparts.
514
515_C/C++_:
516     _Prototype_:  `int omp_in_final(void);'
517
518_Fortran_:
519     _Interface_:  `logical function omp_in_final()'
520
521_Reference_:
522     OpenMP specifications v3.1 (http://www.openmp.org/), section
523     3.2.20.
524
525
526File: libgomp.info,  Node: omp_set_dynamic,  Next: omp_set_max_active_levels,  Prev: omp_in_final,  Up: Runtime Library Routines
527
5282.16 `omp_set_dynamic' - Enable/disable dynamic teams
529=====================================================
530
531_Description_:
532     Enable or disable the dynamic adjustment of the number of threads
533     within a team. The function takes the language-specific equivalent
534     of `true' and `false', where `true' enables dynamic adjustment of
535     team sizes and `false' disables it.
536
537_C/C++_:
538     _Prototype_:  `void omp_set_dynamic(int set);'
539
540_Fortran_:
541     _Interface_:  `subroutine omp_set_dynamic(set)'
542                   `logical, intent(in) :: set'
543
544_See also_:
545     *note OMP_DYNAMIC::, *note omp_get_dynamic::
546
547_Reference_:
548     OpenMP specifications v3.1 (http://www.openmp.org/), section 3.2.7.
549
550
551File: libgomp.info,  Node: omp_set_max_active_levels,  Next: omp_set_nested,  Prev: omp_set_dynamic,  Up: Runtime Library Routines
552
5532.17 `omp_set_max_active_levels' - Limits the number of active parallel regions
554===============================================================================
555
556_Description_:
557     This function limits the maximum allowed number of nested, active
558     parallel regions.
559
560_C/C++_
561     _Prototype_:  `void omp_set_max_active_levels(int max_levels);'
562
563_Fortran_:
564     _Interface_:  `subroutine omp_set_max_active_levels(max_levels)'
565                   `integer max_levels'
566
567_See also_:
568     *note omp_get_max_active_levels::, *note omp_get_active_level::
569
570_Reference_:
571     OpenMP specifications v3.1 (http://www.openmp.org/), section
572     3.2.14.
573
574
575File: libgomp.info,  Node: omp_set_nested,  Next: omp_set_num_threads,  Prev: omp_set_max_active_levels,  Up: Runtime Library Routines
576
5772.18 `omp_set_nested' - Enable/disable nested parallel regions
578==============================================================
579
580_Description_:
581     Enable or disable nested parallel regions, i.e., whether team
582     members are allowed to create new teams. The function takes the
583     language-specific equivalent of `true' and `false', where `true'
584     enables dynamic adjustment of team sizes and `false' disables it.
585
586_C/C++_:
587     _Prototype_:  `void omp_set_nested(int set);'
588
589_Fortran_:
590     _Interface_:  `subroutine omp_set_nested(set)'
591                   `logical, intent(in) :: set'
592
593_See also_:
594     *note OMP_NESTED::, *note omp_get_nested::
595
596_Reference_:
597     OpenMP specifications v3.1 (http://www.openmp.org/), section 3.2.9.
598
599
600File: libgomp.info,  Node: omp_set_num_threads,  Next: omp_set_schedule,  Prev: omp_set_nested,  Up: Runtime Library Routines
601
6022.19 `omp_set_num_threads' - Set upper team size limit
603======================================================
604
605_Description_:
606     Specifies the number of threads used by default in subsequent
607     parallel sections, if those do not specify a `num_threads' clause.
608     The argument of `omp_set_num_threads' shall be a positive integer.
609
610_C/C++_:
611     _Prototype_:  `void omp_set_num_threads(int n);'
612
613_Fortran_:
614     _Interface_:  `subroutine omp_set_num_threads(n)'
615                   `integer, intent(in) :: n'
616
617_See also_:
618     *note OMP_NUM_THREADS::, *note omp_get_num_threads::, *note
619     omp_get_max_threads::
620
621_Reference_:
622     OpenMP specifications v3.1 (http://www.openmp.org/), section 3.2.1.
623
624
625File: libgomp.info,  Node: omp_set_schedule,  Next: omp_init_lock,  Prev: omp_set_num_threads,  Up: Runtime Library Routines
626
6272.20 `omp_set_schedule' - Set the runtime scheduling method
628===========================================================
629
630_Description_:
631     Sets the runtime scheduling method. The KIND argument can have the
632     value `omp_sched_static', `omp_sched_dynamic', `omp_sched_guided'
633     or `omp_sched_auto'. Except for `omp_sched_auto', the chunk size
634     is set to the value of MODIFIER if positive, or to the default
635     value if zero or negative.  For `omp_sched_auto' the MODIFIER
636     argument is ignored.
637
638_C/C++_
639     _Prototype_:  `void omp_set_schedule(omp_sched_t *kind, int
640                   *modifier);'
641
642_Fortran_:
643     _Interface_:  `subroutine omp_set_schedule(kind, modifier)'
644                   `integer(kind=omp_sched_kind) kind'
645                   `integer modifier'
646
647_See also_:
648     *note omp_get_schedule:: *note OMP_SCHEDULE::
649
650_Reference_:
651     OpenMP specifications v3.1 (http://www.openmp.org/), section
652     3.2.11.
653
654
655File: libgomp.info,  Node: omp_init_lock,  Next: omp_set_lock,  Prev: omp_set_schedule,  Up: Runtime Library Routines
656
6572.21 `omp_init_lock' - Initialize simple lock
658=============================================
659
660_Description_:
661     Initialize a simple lock.  After initialization, the lock is in an
662     unlocked state.
663
664_C/C++_:
665     _Prototype_:  `void omp_init_lock(omp_lock_t *lock);'
666
667_Fortran_:
668     _Interface_:  `subroutine omp_init_lock(lock)'
669                   `integer(omp_lock_kind), intent(out) :: lock'
670
671_See also_:
672     *note omp_destroy_lock::
673
674_Reference_:
675     OpenMP specifications v3.1 (http://www.openmp.org/), section 3.3.1.
676
677
678File: libgomp.info,  Node: omp_set_lock,  Next: omp_test_lock,  Prev: omp_init_lock,  Up: Runtime Library Routines
679
6802.22 `omp_set_lock' - Wait for and set simple lock
681==================================================
682
683_Description_:
684     Before setting a simple lock, the lock variable must be
685     initialized by `omp_init_lock'. The calling thread is blocked
686     until the lock is available. If the lock is already held by the
687     current thread, a deadlock occurs.
688
689_C/C++_:
690     _Prototype_:  `void omp_set_lock(omp_lock_t *lock);'
691
692_Fortran_:
693     _Interface_:  `subroutine omp_set_lock(lock)'
694                   `integer(omp_lock_kind), intent(inout) :: lock'
695
696_See also_:
697     *note omp_init_lock::, *note omp_test_lock::, *note
698     omp_unset_lock::
699
700_Reference_:
701     OpenMP specifications v3.1 (http://www.openmp.org/), section 3.3.3.
702
703
704File: libgomp.info,  Node: omp_test_lock,  Next: omp_unset_lock,  Prev: omp_set_lock,  Up: Runtime Library Routines
705
7062.23 `omp_test_lock' - Test and set simple lock if available
707============================================================
708
709_Description_:
710     Before setting a simple lock, the lock variable must be
711     initialized by `omp_init_lock'. Contrary to `omp_set_lock',
712     `omp_test_lock' does not block if the lock is not available. This
713     function returns `true' upon success, `false' otherwise. Here,
714     `true' and `false' represent their language-specific counterparts.
715
716_C/C++_:
717     _Prototype_:  `int omp_test_lock(omp_lock_t *lock);'
718
719_Fortran_:
720     _Interface_:  `logical function omp_test_lock(lock)'
721                   `integer(omp_lock_kind), intent(inout) :: lock'
722
723_See also_:
724     *note omp_init_lock::, *note omp_set_lock::, *note omp_set_lock::
725
726_Reference_:
727     OpenMP specifications v3.1 (http://www.openmp.org/), section 3.3.5.
728
729
730File: libgomp.info,  Node: omp_unset_lock,  Next: omp_destroy_lock,  Prev: omp_test_lock,  Up: Runtime Library Routines
731
7322.24 `omp_unset_lock' - Unset simple lock
733=========================================
734
735_Description_:
736     A simple lock about to be unset must have been locked by
737     `omp_set_lock' or `omp_test_lock' before. In addition, the lock
738     must be held by the thread calling `omp_unset_lock'. Then, the
739     lock becomes unlocked. If one or more threads attempted to set the
740     lock before, one of them is chosen to, again, set the lock to
741     itself.
742
743_C/C++_:
744     _Prototype_:  `void omp_unset_lock(omp_lock_t *lock);'
745
746_Fortran_:
747     _Interface_:  `subroutine omp_unset_lock(lock)'
748                   `integer(omp_lock_kind), intent(inout) :: lock'
749
750_See also_:
751     *note omp_set_lock::, *note omp_test_lock::
752
753_Reference_:
754     OpenMP specifications v3.1 (http://www.openmp.org/), section 3.3.4.
755
756
757File: libgomp.info,  Node: omp_destroy_lock,  Next: omp_init_nest_lock,  Prev: omp_unset_lock,  Up: Runtime Library Routines
758
7592.25 `omp_destroy_lock' - Destroy simple lock
760=============================================
761
762_Description_:
763     Destroy a simple lock. In order to be destroyed, a simple lock
764     must be in the unlocked state.
765
766_C/C++_:
767     _Prototype_:  `void omp_destroy_lock(omp_lock_t *lock);'
768
769_Fortran_:
770     _Interface_:  `subroutine omp_destroy_lock(lock)'
771                   `integer(omp_lock_kind), intent(inout) :: lock'
772
773_See also_:
774     *note omp_init_lock::
775
776_Reference_:
777     OpenMP specifications v3.1 (http://www.openmp.org/), section 3.3.2.
778
779
780File: libgomp.info,  Node: omp_init_nest_lock,  Next: omp_set_nest_lock,  Prev: omp_destroy_lock,  Up: Runtime Library Routines
781
7822.26 `omp_init_nest_lock' - Initialize nested lock
783==================================================
784
785_Description_:
786     Initialize a nested lock.  After initialization, the lock is in an
787     unlocked state and the nesting count is set to zero.
788
789_C/C++_:
790     _Prototype_:  `void omp_init_nest_lock(omp_nest_lock_t *lock);'
791
792_Fortran_:
793     _Interface_:  `subroutine omp_init_nest_lock(lock)'
794                   `integer(omp_nest_lock_kind), intent(out) :: lock'
795
796_See also_:
797     *note omp_destroy_nest_lock::
798
799_Reference_:
800     OpenMP specifications v3.1 (http://www.openmp.org/), section 3.3.1.
801
802
803File: libgomp.info,  Node: omp_set_nest_lock,  Next: omp_test_nest_lock,  Prev: omp_init_nest_lock,  Up: Runtime Library Routines
804
8052.27 `omp_set_nest_lock' - Wait for and set nested lock
806=======================================================
807
808_Description_:
809     Before setting a nested lock, the lock variable must be
810     initialized by `omp_init_nest_lock'. The calling thread is blocked
811     until the lock is available. If the lock is already held by the
812     current thread, the nesting count for the lock is incremented.
813
814_C/C++_:
815     _Prototype_:  `void omp_set_nest_lock(omp_nest_lock_t *lock);'
816
817_Fortran_:
818     _Interface_:  `subroutine omp_set_nest_lock(lock)'
819                   `integer(omp_nest_lock_kind), intent(inout) :: lock'
820
821_See also_:
822     *note omp_init_nest_lock::, *note omp_unset_nest_lock::
823
824_Reference_:
825     OpenMP specifications v3.1 (http://www.openmp.org/), section 3.3.3.
826
827
828File: libgomp.info,  Node: omp_test_nest_lock,  Next: omp_unset_nest_lock,  Prev: omp_set_nest_lock,  Up: Runtime Library Routines
829
8302.28 `omp_test_nest_lock' - Test and set nested lock if available
831=================================================================
832
833_Description_:
834     Before setting a nested lock, the lock variable must be
835     initialized by `omp_init_nest_lock'. Contrary to
836     `omp_set_nest_lock', `omp_test_nest_lock' does not block if the
837     lock is not available.  If the lock is already held by the current
838     thread, the new nesting count is returned. Otherwise, the return
839     value equals zero.
840
841_C/C++_:
842     _Prototype_:  `int omp_test_nest_lock(omp_nest_lock_t *lock);'
843
844_Fortran_:
845     _Interface_:  `logical function omp_test_nest_lock(lock)'
846                   `integer(omp_nest_lock_kind), intent(inout) :: lock'
847
848_See also_:
849     *note omp_init_lock::, *note omp_set_lock::, *note omp_set_lock::
850
851_Reference_:
852     OpenMP specifications v3.1 (http://www.openmp.org/), section 3.3.5.
853
854
855File: libgomp.info,  Node: omp_unset_nest_lock,  Next: omp_destroy_nest_lock,  Prev: omp_test_nest_lock,  Up: Runtime Library Routines
856
8572.29 `omp_unset_nest_lock' - Unset nested lock
858==============================================
859
860_Description_:
861     A nested lock about to be unset must have been locked by
862     `omp_set_nested_lock' or `omp_test_nested_lock' before. In
863     addition, the lock must be held by the thread calling
864     `omp_unset_nested_lock'. If the nesting count drops to zero, the
865     lock becomes unlocked. If one ore more threads attempted to set
866     the lock before, one of them is chosen to, again, set the lock to
867     itself.
868
869_C/C++_:
870     _Prototype_:  `void omp_unset_nest_lock(omp_nest_lock_t *lock);'
871
872_Fortran_:
873     _Interface_:  `subroutine omp_unset_nest_lock(lock)'
874                   `integer(omp_nest_lock_kind), intent(inout) :: lock'
875
876_See also_:
877     *note omp_set_nest_lock::
878
879_Reference_:
880     OpenMP specifications v3.1 (http://www.openmp.org/), section 3.3.4.
881
882
883File: libgomp.info,  Node: omp_destroy_nest_lock,  Next: omp_get_wtick,  Prev: omp_unset_nest_lock,  Up: Runtime Library Routines
884
8852.30 `omp_destroy_nest_lock' - Destroy nested lock
886==================================================
887
888_Description_:
889     Destroy a nested lock. In order to be destroyed, a nested lock
890     must be in the unlocked state and its nesting count must equal
891     zero.
892
893_C/C++_:
894     _Prototype_:  `void omp_destroy_nest_lock(omp_nest_lock_t *);'
895
896_Fortran_:
897     _Interface_:  `subroutine omp_destroy_nest_lock(lock)'
898                   `integer(omp_nest_lock_kind), intent(inout) :: lock'
899
900_See also_:
901     *note omp_init_lock::
902
903_Reference_:
904     OpenMP specifications v3.1 (http://www.openmp.org/), section 3.3.2.
905
906
907File: libgomp.info,  Node: omp_get_wtick,  Next: omp_get_wtime,  Prev: omp_destroy_nest_lock,  Up: Runtime Library Routines
908
9092.31 `omp_get_wtick' - Get timer precision
910==========================================
911
912_Description_:
913     Gets the timer precision, i.e., the number of seconds between two
914     successive clock ticks.
915
916_C/C++_:
917     _Prototype_:  `double omp_get_wtick(void);'
918
919_Fortran_:
920     _Interface_:  `double precision function omp_get_wtick()'
921
922_See also_:
923     *note omp_get_wtime::
924
925_Reference_:
926     OpenMP specifications v3.1 (http://www.openmp.org/), section 3.4.2.
927
928
929File: libgomp.info,  Node: omp_get_wtime,  Prev: omp_get_wtick,  Up: Runtime Library Routines
930
9312.32 `omp_get_wtime' - Elapsed wall clock time
932==============================================
933
934_Description_:
935     Elapsed wall clock time in seconds. The time is measured per
936     thread, no guarantee can be made that two distinct threads measure
937     the same time.  Time is measured from some "time in the past",
938     which is an arbitrary time guaranteed not to change during the
939     execution of the program.
940
941_C/C++_:
942     _Prototype_:  `double omp_get_wtime(void);'
943
944_Fortran_:
945     _Interface_:  `double precision function omp_get_wtime()'
946
947_See also_:
948     *note omp_get_wtick::
949
950_Reference_:
951     OpenMP specifications v3.1 (http://www.openmp.org/), section 3.4.1.
952
953
954File: libgomp.info,  Node: Environment Variables,  Next: The libgomp ABI,  Prev: Runtime Library Routines,  Up: Top
955
9563 Environment Variables
957***********************
958
959The variables `OMP_DYNAMIC', `OMP_MAX_ACTIVE_LEVELS', `OMP_NESTED',
960`OMP_NUM_THREADS', `OMP_SCHEDULE', `OMP_STACKSIZE',`OMP_THREAD_LIMIT'
961and `OMP_WAIT_POLICY' are defined by section 4 of the OpenMP
962specifications in version 3.1, while `GOMP_CPU_AFFINITY' and
963`GOMP_STACKSIZE' are GNU extensions.
964
965* Menu:
966
967* OMP_DYNAMIC::           Dynamic adjustment of threads
968* OMP_MAX_ACTIVE_LEVELS:: Set the maximum number of nested parallel regions
969* OMP_NESTED::            Nested parallel regions
970* OMP_NUM_THREADS::       Specifies the number of threads to use
971* OMP_STACKSIZE::         Set default thread stack size
972* OMP_SCHEDULE::          How threads are scheduled
973* OMP_THREAD_LIMIT::      Set the maximum number of threads
974* OMP_WAIT_POLICY::       How waiting threads are handled
975* OMP_PROC_BIND::         Whether theads may be moved between CPUs
976* GOMP_CPU_AFFINITY::     Bind threads to specific CPUs
977* GOMP_STACKSIZE::        Set default thread stack size
978
979
980File: libgomp.info,  Node: OMP_DYNAMIC,  Next: OMP_MAX_ACTIVE_LEVELS,  Up: Environment Variables
981
9823.1 `OMP_DYNAMIC' - Dynamic adjustment of threads
983=================================================
984
985_Description_:
986     Enable or disable the dynamic adjustment of the number of threads
987     within a team. The value of this environment variable shall be
988     `TRUE' or `FALSE'. If undefined, dynamic adjustment is disabled by
989     default.
990
991_See also_:
992     *note omp_set_dynamic::
993
994_Reference_:
995     OpenMP specifications v3.1 (http://www.openmp.org/), section 4.3
996
997
998File: libgomp.info,  Node: OMP_MAX_ACTIVE_LEVELS,  Next: OMP_NESTED,  Prev: OMP_DYNAMIC,  Up: Environment Variables
999
10003.2 `OMP_MAX_ACTIVE_LEVELS' - Set the maximum number of nested parallel regions
1001===============================================================================
1002
1003_Description_:
1004     Specifies the initial value for the maximum number of nested
1005     parallel regions. The value of this variable shall be a positive
1006     integer.  If undefined, the number of active levels is unlimited.
1007
1008_See also_:
1009     *note omp_set_max_active_levels::
1010
1011_Reference_:
1012     OpenMP specifications v3.1 (http://www.openmp.org/), section 4.8
1013
1014
1015File: libgomp.info,  Node: OMP_NESTED,  Next: OMP_NUM_THREADS,  Prev: OMP_MAX_ACTIVE_LEVELS,  Up: Environment Variables
1016
10173.3 `OMP_NESTED' - Nested parallel regions
1018==========================================
1019
1020_Description_:
1021     Enable or disable nested parallel regions, i.e., whether team
1022     members are allowed to create new teams. The value of this
1023     environment variable shall be `TRUE' or `FALSE'. If undefined,
1024     nested parallel regions are disabled by default.
1025
1026_See also_:
1027     *note omp_set_nested::
1028
1029_Reference_:
1030     OpenMP specifications v3.1 (http://www.openmp.org/), section 4.5
1031
1032
1033File: libgomp.info,  Node: OMP_NUM_THREADS,  Next: OMP_STACKSIZE,  Prev: OMP_NESTED,  Up: Environment Variables
1034
10353.4 `OMP_NUM_THREADS' - Specifies the number of threads to use
1036==============================================================
1037
1038_Description_:
1039     Specifies the default number of threads to use in parallel
1040     regions. The value of this variable shall be a comma-separated
1041     list of positive integers; the value specified the number of
1042     threads to use for the corresponding nested level. If undefined
1043     one thread per CPU is used.
1044
1045_See also_:
1046     *note omp_set_num_threads::
1047
1048_Reference_:
1049     OpenMP specifications v3.1 (http://www.openmp.org/), section 4.2
1050
1051
1052File: libgomp.info,  Node: OMP_SCHEDULE,  Next: OMP_THREAD_LIMIT,  Prev: OMP_STACKSIZE,  Up: Environment Variables
1053
10543.5 `OMP_SCHEDULE' - How threads are scheduled
1055==============================================
1056
1057_Description_:
1058     Allows to specify `schedule type' and `chunk size'.  The value of
1059     the variable shall have the form: `type[,chunk]' where `type' is
1060     one of `static', `dynamic', `guided' or `auto' The optional
1061     `chunk' size shall be a positive integer. If undefined, dynamic
1062     scheduling and a chunk size of 1 is used.
1063
1064_See also_:
1065     *note omp_set_schedule::
1066
1067_Reference_:
1068     OpenMP specifications v3.1 (http://www.openmp.org/), sections
1069     2.5.1 and 4.1
1070
1071
1072File: libgomp.info,  Node: OMP_STACKSIZE,  Next: OMP_SCHEDULE,  Prev: OMP_NUM_THREADS,  Up: Environment Variables
1073
10743.6 `OMP_STACKSIZE' - Set default thread stack size
1075===================================================
1076
1077_Description_:
1078     Set the default thread stack size in kilobytes, unless the number
1079     is suffixed by `B', `K', `M' or `G', in which case the size is,
1080     respectively, in bytes, kilobytes, megabytes or gigabytes. This is
1081     different from `pthread_attr_setstacksize' which gets the number
1082     of bytes as an argument. If the stack size cannot be set due to
1083     system constraints, an error is reported and the initial stack
1084     size is left unchanged. If undefined, the stack size is system
1085     dependent.
1086
1087_Reference_:
1088     OpenMP specifications v3.1 (http://www.openmp.org/), sections 4.6
1089
1090
1091File: libgomp.info,  Node: OMP_THREAD_LIMIT,  Next: OMP_WAIT_POLICY,  Prev: OMP_SCHEDULE,  Up: Environment Variables
1092
10933.7 `OMP_THREAD_LIMIT' - Set the maximum number of threads
1094==========================================================
1095
1096_Description_:
1097     Specifies the number of threads to use for the whole program. The
1098     value of this variable shall be a positive integer. If undefined,
1099     the number of threads is not limited.
1100
1101_See also_:
1102     *note OMP_NUM_THREADS:: *note omp_get_thread_limit::
1103
1104_Reference_:
1105     OpenMP specifications v3.1 (http://www.openmp.org/), section 4.9
1106
1107
1108File: libgomp.info,  Node: OMP_WAIT_POLICY,  Next: OMP_PROC_BIND,  Prev: OMP_THREAD_LIMIT,  Up: Environment Variables
1109
11103.8 `OMP_WAIT_POLICY' - How waiting threads are handled
1111=======================================================
1112
1113_Description_:
1114     Specifies whether waiting threads should be active or passive. If
1115     the value is `PASSIVE', waiting threads should not consume CPU
1116     power while waiting; while the value is `ACTIVE' specifies that
1117     they should.
1118
1119_Reference_:
1120     OpenMP specifications v3.1 (http://www.openmp.org/), sections 4.7
1121
1122
1123File: libgomp.info,  Node: OMP_PROC_BIND,  Next: GOMP_CPU_AFFINITY,  Prev: OMP_WAIT_POLICY,  Up: Environment Variables
1124
11253.9 `OMP_PROC_BIND' - Whether theads may be moved between CPUs
1126==============================================================
1127
1128_Description_:
1129     Specifies whether threads may be moved between processors. If set
1130     to `true', OpenMP theads should not be moved, if set to `false'
1131     they may be moved.
1132
1133_See also_:
1134     *note GOMP_CPU_AFFINITY::
1135
1136_Reference_:
1137     OpenMP specifications v3.1 (http://www.openmp.org/), sections 4.4
1138
1139
1140File: libgomp.info,  Node: GOMP_CPU_AFFINITY,  Next: GOMP_STACKSIZE,  Prev: OMP_PROC_BIND,  Up: Environment Variables
1141
11423.10 `GOMP_CPU_AFFINITY' - Bind threads to specific CPUs
1143========================================================
1144
1145_Description_:
1146     Binds threads to specific CPUs. The variable should contain a
1147     space-separated or comma-separated list of CPUs. This list may
1148     contain different kinds of entries: either single CPU numbers in
1149     any order, a range of CPUs (M-N) or a range with some stride
1150     (M-N:S).  CPU numbers are zero based. For example,
1151     `GOMP_CPU_AFFINITY="0 3 1-2 4-15:2"' will bind the initial thread
1152     to CPU 0, the second to CPU 3, the third to CPU 1, the fourth to
1153     CPU 2, the fifth to CPU 4, the sixth through tenth to CPUs 6, 8,
1154     10, 12, and 14 respectively and then start assigning back from the
1155     beginning of the list.  `GOMP_CPU_AFFINITY=0' binds all threads to
1156     CPU 0.
1157
1158     There is no GNU OpenMP library routine to determine whether a CPU
1159     affinity specification is in effect. As a workaround,
1160     language-specific library functions, e.g., `getenv' in C or
1161     `GET_ENVIRONMENT_VARIABLE' in Fortran, may be used to query the
1162     setting of the `GOMP_CPU_AFFINITY' environment variable. A defined
1163     CPU affinity on startup cannot be changed or disabled during the
1164     runtime of the application.
1165
1166     If this environment variable is omitted, the host system will
1167     handle the assignment of threads to CPUs.
1168
1169_See also_:
1170     *note OMP_PROC_BIND::
1171
1172
1173File: libgomp.info,  Node: GOMP_STACKSIZE,  Prev: GOMP_CPU_AFFINITY,  Up: Environment Variables
1174
11753.11 `GOMP_STACKSIZE' - Set default thread stack size
1176=====================================================
1177
1178_Description_:
1179     Set the default thread stack size in kilobytes. This is different
1180     from `pthread_attr_setstacksize' which gets the number of bytes as
1181     an argument. If the stack size cannot be set due to system
1182     constraints, an error is reported and the initial stack size is
1183     left unchanged. If undefined, the stack size is system dependent.
1184
1185_See also_:
1186     *note OMP_STACKSIZE::
1187
1188_Reference_:
1189     GCC Patches Mailinglist
1190     (http://gcc.gnu.org/ml/gcc-patches/2006-06/msg00493.html), GCC
1191     Patches Mailinglist
1192     (http://gcc.gnu.org/ml/gcc-patches/2006-06/msg00496.html)
1193
1194
1195File: libgomp.info,  Node: The libgomp ABI,  Next: Reporting Bugs,  Prev: Environment Variables,  Up: Top
1196
11974 The libgomp ABI
1198*****************
1199
1200The following sections present notes on the external ABI as presented
1201by libgomp.  Only maintainers should need them.
1202
1203* Menu:
1204
1205* Implementing MASTER construct::
1206* Implementing CRITICAL construct::
1207* Implementing ATOMIC construct::
1208* Implementing FLUSH construct::
1209* Implementing BARRIER construct::
1210* Implementing THREADPRIVATE construct::
1211* Implementing PRIVATE clause::
1212* Implementing FIRSTPRIVATE LASTPRIVATE COPYIN and COPYPRIVATE clauses::
1213* Implementing REDUCTION clause::
1214* Implementing PARALLEL construct::
1215* Implementing FOR construct::
1216* Implementing ORDERED construct::
1217* Implementing SECTIONS construct::
1218* Implementing SINGLE construct::
1219
1220
1221File: libgomp.info,  Node: Implementing MASTER construct,  Next: Implementing CRITICAL construct,  Up: The libgomp ABI
1222
12234.1 Implementing MASTER construct
1224=================================
1225
1226     if (omp_get_thread_num () == 0)
1227       block
1228
1229   Alternately, we generate two copies of the parallel subfunction and
1230only include this in the version run by the master thread.  Surely this
1231is not worthwhile though...
1232
1233
1234File: libgomp.info,  Node: Implementing CRITICAL construct,  Next: Implementing ATOMIC construct,  Prev: Implementing MASTER construct,  Up: The libgomp ABI
1235
12364.2 Implementing CRITICAL construct
1237===================================
1238
1239Without a specified name,
1240
1241       void GOMP_critical_start (void);
1242       void GOMP_critical_end (void);
1243
1244   so that we don't get COPY relocations from libgomp to the main
1245application.
1246
1247   With a specified name, use omp_set_lock and omp_unset_lock with name
1248being transformed into a variable declared like
1249
1250       omp_lock_t gomp_critical_user_<name> __attribute__((common))
1251
1252   Ideally the ABI would specify that all zero is a valid unlocked
1253state, and so we wouldn't need to initialize this at startup.
1254
1255
1256File: libgomp.info,  Node: Implementing ATOMIC construct,  Next: Implementing FLUSH construct,  Prev: Implementing CRITICAL construct,  Up: The libgomp ABI
1257
12584.3 Implementing ATOMIC construct
1259=================================
1260
1261The target should implement the `__sync' builtins.
1262
1263   Failing that we could add
1264
1265       void GOMP_atomic_enter (void)
1266       void GOMP_atomic_exit (void)
1267
1268   which reuses the regular lock code, but with yet another lock object
1269private to the library.
1270
1271
1272File: libgomp.info,  Node: Implementing FLUSH construct,  Next: Implementing BARRIER construct,  Prev: Implementing ATOMIC construct,  Up: The libgomp ABI
1273
12744.4 Implementing FLUSH construct
1275================================
1276
1277Expands to the `__sync_synchronize' builtin.
1278
1279
1280File: libgomp.info,  Node: Implementing BARRIER construct,  Next: Implementing THREADPRIVATE construct,  Prev: Implementing FLUSH construct,  Up: The libgomp ABI
1281
12824.5 Implementing BARRIER construct
1283==================================
1284
1285       void GOMP_barrier (void)
1286
1287
1288File: libgomp.info,  Node: Implementing THREADPRIVATE construct,  Next: Implementing PRIVATE clause,  Prev: Implementing BARRIER construct,  Up: The libgomp ABI
1289
12904.6 Implementing THREADPRIVATE construct
1291========================================
1292
1293In _most_ cases we can map this directly to `__thread'.  Except that
1294OMP allows constructors for C++ objects.  We can either refuse to
1295support this (how often is it used?) or we can implement something akin
1296to .ctors.
1297
1298   Even more ideally, this ctor feature is handled by extensions to the
1299main pthreads library.  Failing that, we can have a set of entry points
1300to register ctor functions to be called.
1301
1302
1303File: libgomp.info,  Node: Implementing PRIVATE clause,  Next: Implementing FIRSTPRIVATE LASTPRIVATE COPYIN and COPYPRIVATE clauses,  Prev: Implementing THREADPRIVATE construct,  Up: The libgomp ABI
1304
13054.7 Implementing PRIVATE clause
1306===============================
1307
1308In association with a PARALLEL, or within the lexical extent of a
1309PARALLEL block, the variable becomes a local variable in the parallel
1310subfunction.
1311
1312   In association with FOR or SECTIONS blocks, create a new automatic
1313variable within the current function.  This preserves the semantic of
1314new variable creation.
1315
1316
1317File: libgomp.info,  Node: Implementing FIRSTPRIVATE LASTPRIVATE COPYIN and COPYPRIVATE clauses,  Next: Implementing REDUCTION clause,  Prev: Implementing PRIVATE clause,  Up: The libgomp ABI
1318
13194.8 Implementing FIRSTPRIVATE LASTPRIVATE COPYIN and COPYPRIVATE clauses
1320========================================================================
1321
1322This seems simple enough for PARALLEL blocks.  Create a private struct
1323for communicating between the parent and subfunction.  In the parent,
1324copy in values for scalar and "small" structs; copy in addresses for
1325others TREE_ADDRESSABLE types.  In the subfunction, copy the value into
1326the local variable.
1327
1328   It is not clear what to do with bare FOR or SECTION blocks.  The
1329only thing I can figure is that we do something like:
1330
1331     #pragma omp for firstprivate(x) lastprivate(y)
1332     for (int i = 0; i < n; ++i)
1333       body;
1334
1335   which becomes
1336
1337     {
1338       int x = x, y;
1339
1340       // for stuff
1341
1342       if (i == n)
1343         y = y;
1344     }
1345
1346   where the "x=x" and "y=y" assignments actually have different uids
1347for the two variables, i.e. not something you could write directly in
1348C.  Presumably this only makes sense if the "outer" x and y are global
1349variables.
1350
1351   COPYPRIVATE would work the same way, except the structure broadcast
1352would have to happen via SINGLE machinery instead.
1353
1354
1355File: libgomp.info,  Node: Implementing REDUCTION clause,  Next: Implementing PARALLEL construct,  Prev: Implementing FIRSTPRIVATE LASTPRIVATE COPYIN and COPYPRIVATE clauses,  Up: The libgomp ABI
1356
13574.9 Implementing REDUCTION clause
1358=================================
1359
1360The private struct mentioned in the previous section should have a
1361pointer to an array of the type of the variable, indexed by the
1362thread's TEAM_ID.  The thread stores its final value into the array,
1363and after the barrier, the master thread iterates over the array to
1364collect the values.
1365
1366
1367File: libgomp.info,  Node: Implementing PARALLEL construct,  Next: Implementing FOR construct,  Prev: Implementing REDUCTION clause,  Up: The libgomp ABI
1368
13694.10 Implementing PARALLEL construct
1370====================================
1371
1372       #pragma omp parallel
1373       {
1374         body;
1375       }
1376
1377   becomes
1378
1379       void subfunction (void *data)
1380       {
1381         use data;
1382         body;
1383       }
1384
1385       setup data;
1386       GOMP_parallel_start (subfunction, &data, num_threads);
1387       subfunction (&data);
1388       GOMP_parallel_end ();
1389
1390       void GOMP_parallel_start (void (*fn)(void *), void *data, unsigned num_threads)
1391
1392   The FN argument is the subfunction to be run in parallel.
1393
1394   The DATA argument is a pointer to a structure used to communicate
1395data in and out of the subfunction, as discussed above with respect to
1396FIRSTPRIVATE et al.
1397
1398   The NUM_THREADS argument is 1 if an IF clause is present and false,
1399or the value of the NUM_THREADS clause, if present, or 0.
1400
1401   The function needs to create the appropriate number of threads
1402and/or launch them from the dock.  It needs to create the team
1403structure and assign team ids.
1404
1405       void GOMP_parallel_end (void)
1406
1407   Tears down the team and returns us to the previous
1408`omp_in_parallel()' state.
1409
1410
1411File: libgomp.info,  Node: Implementing FOR construct,  Next: Implementing ORDERED construct,  Prev: Implementing PARALLEL construct,  Up: The libgomp ABI
1412
14134.11 Implementing FOR construct
1414===============================
1415
1416       #pragma omp parallel for
1417       for (i = lb; i <= ub; i++)
1418         body;
1419
1420   becomes
1421
1422       void subfunction (void *data)
1423       {
1424         long _s0, _e0;
1425         while (GOMP_loop_static_next (&_s0, &_e0))
1426         {
1427           long _e1 = _e0, i;
1428           for (i = _s0; i < _e1; i++)
1429             body;
1430         }
1431         GOMP_loop_end_nowait ();
1432       }
1433
1434       GOMP_parallel_loop_static (subfunction, NULL, 0, lb, ub+1, 1, 0);
1435       subfunction (NULL);
1436       GOMP_parallel_end ();
1437
1438       #pragma omp for schedule(runtime)
1439       for (i = 0; i < n; i++)
1440         body;
1441
1442   becomes
1443
1444       {
1445         long i, _s0, _e0;
1446         if (GOMP_loop_runtime_start (0, n, 1, &_s0, &_e0))
1447           do {
1448             long _e1 = _e0;
1449             for (i = _s0, i < _e0; i++)
1450               body;
1451           } while (GOMP_loop_runtime_next (&_s0, _&e0));
1452         GOMP_loop_end ();
1453       }
1454
1455   Note that while it looks like there is trickiness to propagating a
1456non-constant STEP, there isn't really.  We're explicitly allowed to
1457evaluate it as many times as we want, and any variables involved should
1458automatically be handled as PRIVATE or SHARED like any other variables.
1459So the expression should remain evaluable in the subfunction.  We can
1460also pull it into a local variable if we like, but since its supposed
1461to remain unchanged, we can also not if we like.
1462
1463   If we have SCHEDULE(STATIC), and no ORDERED, then we ought to be
1464able to get away with no work-sharing context at all, since we can
1465simply perform the arithmetic directly in each thread to divide up the
1466iterations.  Which would mean that we wouldn't need to call any of
1467these routines.
1468
1469   There are separate routines for handling loops with an ORDERED
1470clause.  Bookkeeping for that is non-trivial...
1471
1472
1473File: libgomp.info,  Node: Implementing ORDERED construct,  Next: Implementing SECTIONS construct,  Prev: Implementing FOR construct,  Up: The libgomp ABI
1474
14754.12 Implementing ORDERED construct
1476===================================
1477
1478       void GOMP_ordered_start (void)
1479       void GOMP_ordered_end (void)
1480
1481
1482File: libgomp.info,  Node: Implementing SECTIONS construct,  Next: Implementing SINGLE construct,  Prev: Implementing ORDERED construct,  Up: The libgomp ABI
1483
14844.13 Implementing SECTIONS construct
1485====================================
1486
1487A block as
1488
1489       #pragma omp sections
1490       {
1491         #pragma omp section
1492         stmt1;
1493         #pragma omp section
1494         stmt2;
1495         #pragma omp section
1496         stmt3;
1497       }
1498
1499   becomes
1500
1501       for (i = GOMP_sections_start (3); i != 0; i = GOMP_sections_next ())
1502         switch (i)
1503           {
1504           case 1:
1505             stmt1;
1506             break;
1507           case 2:
1508             stmt2;
1509             break;
1510           case 3:
1511             stmt3;
1512             break;
1513           }
1514       GOMP_barrier ();
1515
1516
1517File: libgomp.info,  Node: Implementing SINGLE construct,  Prev: Implementing SECTIONS construct,  Up: The libgomp ABI
1518
15194.14 Implementing SINGLE construct
1520==================================
1521
1522A block like
1523
1524       #pragma omp single
1525       {
1526         body;
1527       }
1528
1529   becomes
1530
1531       if (GOMP_single_start ())
1532         body;
1533       GOMP_barrier ();
1534
1535   while
1536
1537       #pragma omp single copyprivate(x)
1538         body;
1539
1540   becomes
1541
1542       datap = GOMP_single_copy_start ();
1543       if (datap == NULL)
1544         {
1545           body;
1546           data.x = x;
1547           GOMP_single_copy_end (&data);
1548         }
1549       else
1550         x = datap->x;
1551       GOMP_barrier ();
1552
1553
1554File: libgomp.info,  Node: Reporting Bugs,  Next: Copying,  Prev: The libgomp ABI,  Up: Top
1555
15565 Reporting Bugs
1557****************
1558
1559Bugs in the GNU OpenMP implementation should be reported via bugzilla
1560(http://gcc.gnu.org/bugzilla/).  For all cases, please add "openmp" to
1561the keywords field in the bug report.
1562
1563
1564File: libgomp.info,  Node: Copying,  Next: GNU Free Documentation License,  Prev: Reporting Bugs,  Up: Top
1565
1566GNU General Public License
1567**************************
1568
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1890     way in which the particular user actually uses, or expects or is
1891     expected to use, the product.  A product is a consumer product
1892     regardless of whether the product has substantial commercial,
1893     industrial or non-consumer uses, unless such uses represent the
1894     only significant mode of use of the product.
1895
1896     "Installation Information" for a User Product means any methods,
1897     procedures, authorization keys, or other information required to
1898     install and execute modified versions of a covered work in that
1899     User Product from a modified version of its Corresponding Source.
1900     The information must suffice to ensure that the continued
1901     functioning of the modified object code is in no case prevented or
1902     interfered with solely because modification has been made.
1903
1904     If you convey an object code work under this section in, or with,
1905     or specifically for use in, a User Product, and the conveying
1906     occurs as part of a transaction in which the right of possession
1907     and use of the User Product is transferred to the recipient in
1908     perpetuity or for a fixed term (regardless of how the transaction
1909     is characterized), the Corresponding Source conveyed under this
1910     section must be accompanied by the Installation Information.  But
1911     this requirement does not apply if neither you nor any third party
1912     retains the ability to install modified object code on the User
1913     Product (for example, the work has been installed in ROM).
1914
1915     The requirement to provide Installation Information does not
1916     include a requirement to continue to provide support service,
1917     warranty, or updates for a work that has been modified or
1918     installed by the recipient, or for the User Product in which it
1919     has been modified or installed.  Access to a network may be denied
1920     when the modification itself materially and adversely affects the
1921     operation of the network or violates the rules and protocols for
1922     communication across the network.
1923
1924     Corresponding Source conveyed, and Installation Information
1925     provided, in accord with this section must be in a format that is
1926     publicly documented (and with an implementation available to the
1927     public in source code form), and must require no special password
1928     or key for unpacking, reading or copying.
1929
1930  7. Additional Terms.
1931
1932     "Additional permissions" are terms that supplement the terms of
1933     this License by making exceptions from one or more of its
1934     conditions.  Additional permissions that are applicable to the
1935     entire Program shall be treated as though they were included in
1936     this License, to the extent that they are valid under applicable
1937     law.  If additional permissions apply only to part of the Program,
1938     that part may be used separately under those permissions, but the
1939     entire Program remains governed by this License without regard to
1940     the additional permissions.
1941
1942     When you convey a copy of a covered work, you may at your option
1943     remove any additional permissions from that copy, or from any part
1944     of it.  (Additional permissions may be written to require their own
1945     removal in certain cases when you modify the work.)  You may place
1946     additional permissions on material, added by you to a covered work,
1947     for which you have or can give appropriate copyright permission.
1948
1949     Notwithstanding any other provision of this License, for material
1950     you add to a covered work, you may (if authorized by the copyright
1951     holders of that material) supplement the terms of this License
1952     with terms:
1953
1954       a. Disclaiming warranty or limiting liability differently from
1955          the terms of sections 15 and 16 of this License; or
1956
1957       b. Requiring preservation of specified reasonable legal notices
1958          or author attributions in that material or in the Appropriate
1959          Legal Notices displayed by works containing it; or
1960
1961       c. Prohibiting misrepresentation of the origin of that material,
1962          or requiring that modified versions of such material be
1963          marked in reasonable ways as different from the original
1964          version; or
1965
1966       d. Limiting the use for publicity purposes of names of licensors
1967          or authors of the material; or
1968
1969       e. Declining to grant rights under trademark law for use of some
1970          trade names, trademarks, or service marks; or
1971
1972       f. Requiring indemnification of licensors and authors of that
1973          material by anyone who conveys the material (or modified
1974          versions of it) with contractual assumptions of liability to
1975          the recipient, for any liability that these contractual
1976          assumptions directly impose on those licensors and authors.
1977
1978     All other non-permissive additional terms are considered "further
1979     restrictions" within the meaning of section 10.  If the Program as
1980     you received it, or any part of it, contains a notice stating that
1981     it is governed by this License along with a term that is a further
1982     restriction, you may remove that term.  If a license document
1983     contains a further restriction but permits relicensing or
1984     conveying under this License, you may add to a covered work
1985     material governed by the terms of that license document, provided
1986     that the further restriction does not survive such relicensing or
1987     conveying.
1988
1989     If you add terms to a covered work in accord with this section, you
1990     must place, in the relevant source files, a statement of the
1991     additional terms that apply to those files, or a notice indicating
1992     where to find the applicable terms.
1993
1994     Additional terms, permissive or non-permissive, may be stated in
1995     the form of a separately written license, or stated as exceptions;
1996     the above requirements apply either way.
1997
1998  8. Termination.
1999
2000     You may not propagate or modify a covered work except as expressly
2001     provided under this License.  Any attempt otherwise to propagate or
2002     modify it is void, and will automatically terminate your rights
2003     under this License (including any patent licenses granted under
2004     the third paragraph of section 11).
2005
2006     However, if you cease all violation of this License, then your
2007     license from a particular copyright holder is reinstated (a)
2008     provisionally, unless and until the copyright holder explicitly
2009     and finally terminates your license, and (b) permanently, if the
2010     copyright holder fails to notify you of the violation by some
2011     reasonable means prior to 60 days after the cessation.
2012
2013     Moreover, your license from a particular copyright holder is
2014     reinstated permanently if the copyright holder notifies you of the
2015     violation by some reasonable means, this is the first time you have
2016     received notice of violation of this License (for any work) from
2017     that copyright holder, and you cure the violation prior to 30 days
2018     after your receipt of the notice.
2019
2020     Termination of your rights under this section does not terminate
2021     the licenses of parties who have received copies or rights from
2022     you under this License.  If your rights have been terminated and
2023     not permanently reinstated, you do not qualify to receive new
2024     licenses for the same material under section 10.
2025
2026  9. Acceptance Not Required for Having Copies.
2027
2028     You are not required to accept this License in order to receive or
2029     run a copy of the Program.  Ancillary propagation of a covered work
2030     occurring solely as a consequence of using peer-to-peer
2031     transmission to receive a copy likewise does not require
2032     acceptance.  However, nothing other than this License grants you
2033     permission to propagate or modify any covered work.  These actions
2034     infringe copyright if you do not accept this License.  Therefore,
2035     by modifying or propagating a covered work, you indicate your
2036     acceptance of this License to do so.
2037
2038 10. Automatic Licensing of Downstream Recipients.
2039
2040     Each time you convey a covered work, the recipient automatically
2041     receives a license from the original licensors, to run, modify and
2042     propagate that work, subject to this License.  You are not
2043     responsible for enforcing compliance by third parties with this
2044     License.
2045
2046     An "entity transaction" is a transaction transferring control of an
2047     organization, or substantially all assets of one, or subdividing an
2048     organization, or merging organizations.  If propagation of a
2049     covered work results from an entity transaction, each party to that
2050     transaction who receives a copy of the work also receives whatever
2051     licenses to the work the party's predecessor in interest had or
2052     could give under the previous paragraph, plus a right to
2053     possession of the Corresponding Source of the work from the
2054     predecessor in interest, if the predecessor has it or can get it
2055     with reasonable efforts.
2056
2057     You may not impose any further restrictions on the exercise of the
2058     rights granted or affirmed under this License.  For example, you
2059     may not impose a license fee, royalty, or other charge for
2060     exercise of rights granted under this License, and you may not
2061     initiate litigation (including a cross-claim or counterclaim in a
2062     lawsuit) alleging that any patent claim is infringed by making,
2063     using, selling, offering for sale, or importing the Program or any
2064     portion of it.
2065
2066 11. Patents.
2067
2068     A "contributor" is a copyright holder who authorizes use under this
2069     License of the Program or a work on which the Program is based.
2070     The work thus licensed is called the contributor's "contributor
2071     version".
2072
2073     A contributor's "essential patent claims" are all patent claims
2074     owned or controlled by the contributor, whether already acquired or
2075     hereafter acquired, that would be infringed by some manner,
2076     permitted by this License, of making, using, or selling its
2077     contributor version, but do not include claims that would be
2078     infringed only as a consequence of further modification of the
2079     contributor version.  For purposes of this definition, "control"
2080     includes the right to grant patent sublicenses in a manner
2081     consistent with the requirements of this License.
2082
2083     Each contributor grants you a non-exclusive, worldwide,
2084     royalty-free patent license under the contributor's essential
2085     patent claims, to make, use, sell, offer for sale, import and
2086     otherwise run, modify and propagate the contents of its
2087     contributor version.
2088
2089     In the following three paragraphs, a "patent license" is any
2090     express agreement or commitment, however denominated, not to
2091     enforce a patent (such as an express permission to practice a
2092     patent or covenant not to sue for patent infringement).  To
2093     "grant" such a patent license to a party means to make such an
2094     agreement or commitment not to enforce a patent against the party.
2095
2096     If you convey a covered work, knowingly relying on a patent
2097     license, and the Corresponding Source of the work is not available
2098     for anyone to copy, free of charge and under the terms of this
2099     License, through a publicly available network server or other
2100     readily accessible means, then you must either (1) cause the
2101     Corresponding Source to be so available, or (2) arrange to deprive
2102     yourself of the benefit of the patent license for this particular
2103     work, or (3) arrange, in a manner consistent with the requirements
2104     of this License, to extend the patent license to downstream
2105     recipients.  "Knowingly relying" means you have actual knowledge
2106     that, but for the patent license, your conveying the covered work
2107     in a country, or your recipient's use of the covered work in a
2108     country, would infringe one or more identifiable patents in that
2109     country that you have reason to believe are valid.
2110
2111     If, pursuant to or in connection with a single transaction or
2112     arrangement, you convey, or propagate by procuring conveyance of, a
2113     covered work, and grant a patent license to some of the parties
2114     receiving the covered work authorizing them to use, propagate,
2115     modify or convey a specific copy of the covered work, then the
2116     patent license you grant is automatically extended to all
2117     recipients of the covered work and works based on it.
2118
2119     A patent license is "discriminatory" if it does not include within
2120     the scope of its coverage, prohibits the exercise of, or is
2121     conditioned on the non-exercise of one or more of the rights that
2122     are specifically granted under this License.  You may not convey a
2123     covered work if you are a party to an arrangement with a third
2124     party that is in the business of distributing software, under
2125     which you make payment to the third party based on the extent of
2126     your activity of conveying the work, and under which the third
2127     party grants, to any of the parties who would receive the covered
2128     work from you, a discriminatory patent license (a) in connection
2129     with copies of the covered work conveyed by you (or copies made
2130     from those copies), or (b) primarily for and in connection with
2131     specific products or compilations that contain the covered work,
2132     unless you entered into that arrangement, or that patent license
2133     was granted, prior to 28 March 2007.
2134
2135     Nothing in this License shall be construed as excluding or limiting
2136     any implied license or other defenses to infringement that may
2137     otherwise be available to you under applicable patent law.
2138
2139 12. No Surrender of Others' Freedom.
2140
2141     If conditions are imposed on you (whether by court order,
2142     agreement or otherwise) that contradict the conditions of this
2143     License, they do not excuse you from the conditions of this
2144     License.  If you cannot convey a covered work so as to satisfy
2145     simultaneously your obligations under this License and any other
2146     pertinent obligations, then as a consequence you may not convey it
2147     at all.  For example, if you agree to terms that obligate you to
2148     collect a royalty for further conveying from those to whom you
2149     convey the Program, the only way you could satisfy both those
2150     terms and this License would be to refrain entirely from conveying
2151     the Program.
2152
2153 13. Use with the GNU Affero General Public License.
2154
2155     Notwithstanding any other provision of this License, you have
2156     permission to link or combine any covered work with a work licensed
2157     under version 3 of the GNU Affero General Public License into a
2158     single combined work, and to convey the resulting work.  The terms
2159     of this License will continue to apply to the part which is the
2160     covered work, but the special requirements of the GNU Affero
2161     General Public License, section 13, concerning interaction through
2162     a network will apply to the combination as such.
2163
2164 14. Revised Versions of this License.
2165
2166     The Free Software Foundation may publish revised and/or new
2167     versions of the GNU General Public License from time to time.
2168     Such new versions will be similar in spirit to the present
2169     version, but may differ in detail to address new problems or
2170     concerns.
2171
2172     Each version is given a distinguishing version number.  If the
2173     Program specifies that a certain numbered version of the GNU
2174     General Public License "or any later version" applies to it, you
2175     have the option of following the terms and conditions either of
2176     that numbered version or of any later version published by the
2177     Free Software Foundation.  If the Program does not specify a
2178     version number of the GNU General Public License, you may choose
2179     any version ever published by the Free Software Foundation.
2180
2181     If the Program specifies that a proxy can decide which future
2182     versions of the GNU General Public License can be used, that
2183     proxy's public statement of acceptance of a version permanently
2184     authorizes you to choose that version for the Program.
2185
2186     Later license versions may give you additional or different
2187     permissions.  However, no additional obligations are imposed on any
2188     author or copyright holder as a result of your choosing to follow a
2189     later version.
2190
2191 15. Disclaimer of Warranty.
2192
2193     THERE IS NO WARRANTY FOR THE PROGRAM, TO THE EXTENT PERMITTED BY
2194     APPLICABLE LAW.  EXCEPT WHEN OTHERWISE STATED IN WRITING THE
2195     COPYRIGHT HOLDERS AND/OR OTHER PARTIES PROVIDE THE PROGRAM "AS IS"
2196     WITHOUT WARRANTY OF ANY KIND, EITHER EXPRESSED OR IMPLIED,
2197     INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
2198     MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.  THE ENTIRE
2199     RISK AS TO THE QUALITY AND PERFORMANCE OF THE PROGRAM IS WITH YOU.
2200     SHOULD THE PROGRAM PROVE DEFECTIVE, YOU ASSUME THE COST OF ALL
2201     NECESSARY SERVICING, REPAIR OR CORRECTION.
2202
2203 16. Limitation of Liability.
2204
2205     IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN
2206     WRITING WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MODIFIES
2207     AND/OR CONVEYS THE PROGRAM AS PERMITTED ABOVE, BE LIABLE TO YOU
2208     FOR DAMAGES, INCLUDING ANY GENERAL, SPECIAL, INCIDENTAL OR
2209     CONSEQUENTIAL DAMAGES ARISING OUT OF THE USE OR INABILITY TO USE
2210     THE PROGRAM (INCLUDING BUT NOT LIMITED TO LOSS OF DATA OR DATA
2211     BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY YOU OR THIRD
2212     PARTIES OR A FAILURE OF THE PROGRAM TO OPERATE WITH ANY OTHER
2213     PROGRAMS), EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF
2214     THE POSSIBILITY OF SUCH DAMAGES.
2215
2216 17. Interpretation of Sections 15 and 16.
2217
2218     If the disclaimer of warranty and limitation of liability provided
2219     above cannot be given local legal effect according to their terms,
2220     reviewing courts shall apply local law that most closely
2221     approximates an absolute waiver of all civil liability in
2222     connection with the Program, unless a warranty or assumption of
2223     liability accompanies a copy of the Program in return for a fee.
2224
2225
2226END OF TERMS AND CONDITIONS
2227===========================
2228
2229How to Apply These Terms to Your New Programs
2230=============================================
2231
2232If you develop a new program, and you want it to be of the greatest
2233possible use to the public, the best way to achieve this is to make it
2234free software which everyone can redistribute and change under these
2235terms.
2236
2237   To do so, attach the following notices to the program.  It is safest
2238to attach them to the start of each source file to most effectively
2239state the exclusion of warranty; and each file should have at least the
2240"copyright" line and a pointer to where the full notice is found.
2241
2242     ONE LINE TO GIVE THE PROGRAM'S NAME AND A BRIEF IDEA OF WHAT IT DOES.
2243     Copyright (C) YEAR NAME OF AUTHOR
2244
2245     This program is free software: you can redistribute it and/or modify
2246     it under the terms of the GNU General Public License as published by
2247     the Free Software Foundation, either version 3 of the License, or (at
2248     your option) any later version.
2249
2250     This program is distributed in the hope that it will be useful, but
2251     WITHOUT ANY WARRANTY; without even the implied warranty of
2252     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
2253     General Public License for more details.
2254
2255     You should have received a copy of the GNU General Public License
2256     along with this program.  If not, see `http://www.gnu.org/licenses/'.
2257
2258   Also add information on how to contact you by electronic and paper
2259mail.
2260
2261   If the program does terminal interaction, make it output a short
2262notice like this when it starts in an interactive mode:
2263
2264     PROGRAM Copyright (C) YEAR NAME OF AUTHOR
2265     This program comes with ABSOLUTELY NO WARRANTY; for details type `show w'.
2266     This is free software, and you are welcome to redistribute it
2267     under certain conditions; type `show c' for details.
2268
2269   The hypothetical commands `show w' and `show c' should show the
2270appropriate parts of the General Public License.  Of course, your
2271program's commands might be different; for a GUI interface, you would
2272use an "about box".
2273
2274   You should also get your employer (if you work as a programmer) or
2275school, if any, to sign a "copyright disclaimer" for the program, if
2276necessary.  For more information on this, and how to apply and follow
2277the GNU GPL, see `http://www.gnu.org/licenses/'.
2278
2279   The GNU General Public License does not permit incorporating your
2280program into proprietary programs.  If your program is a subroutine
2281library, you may consider it more useful to permit linking proprietary
2282applications with the library.  If this is what you want to do, use the
2283GNU Lesser General Public License instead of this License.  But first,
2284please read `http://www.gnu.org/philosophy/why-not-lgpl.html'.
2285
2286
2287File: libgomp.info,  Node: GNU Free Documentation License,  Next: Funding,  Prev: Copying,  Up: Top
2288
2289GNU Free Documentation License
2290******************************
2291
2292                     Version 1.3, 3 November 2008
2293
2294     Copyright (C) 2000, 2001, 2002, 2007, 2008 Free Software Foundation, Inc.
2295     `http://fsf.org/'
2296
2297     Everyone is permitted to copy and distribute verbatim copies
2298     of this license document, but changing it is not allowed.
2299
2300  0. PREAMBLE
2301
2302     The purpose of this License is to make a manual, textbook, or other
2303     functional and useful document "free" in the sense of freedom: to
2304     assure everyone the effective freedom to copy and redistribute it,
2305     with or without modifying it, either commercially or
2306     noncommercially.  Secondarily, this License preserves for the
2307     author and publisher a way to get credit for their work, while not
2308     being considered responsible for modifications made by others.
2309
2310     This License is a kind of "copyleft", which means that derivative
2311     works of the document must themselves be free in the same sense.
2312     It complements the GNU General Public License, which is a copyleft
2313     license designed for free software.
2314
2315     We have designed this License in order to use it for manuals for
2316     free software, because free software needs free documentation: a
2317     free program should come with manuals providing the same freedoms
2318     that the software does.  But this License is not limited to
2319     software manuals; it can be used for any textual work, regardless
2320     of subject matter or whether it is published as a printed book.
2321     We recommend this License principally for works whose purpose is
2322     instruction or reference.
2323
2324  1. APPLICABILITY AND DEFINITIONS
2325
2326     This License applies to any manual or other work, in any medium,
2327     that contains a notice placed by the copyright holder saying it
2328     can be distributed under the terms of this License.  Such a notice
2329     grants a world-wide, royalty-free license, unlimited in duration,
2330     to use that work under the conditions stated herein.  The
2331     "Document", below, refers to any such manual or work.  Any member
2332     of the public is a licensee, and is addressed as "you".  You
2333     accept the license if you copy, modify or distribute the work in a
2334     way requiring permission under copyright law.
2335
2336     A "Modified Version" of the Document means any work containing the
2337     Document or a portion of it, either copied verbatim, or with
2338     modifications and/or translated into another language.
2339
2340     A "Secondary Section" is a named appendix or a front-matter section
2341     of the Document that deals exclusively with the relationship of the
2342     publishers or authors of the Document to the Document's overall
2343     subject (or to related matters) and contains nothing that could
2344     fall directly within that overall subject.  (Thus, if the Document
2345     is in part a textbook of mathematics, a Secondary Section may not
2346     explain any mathematics.)  The relationship could be a matter of
2347     historical connection with the subject or with related matters, or
2348     of legal, commercial, philosophical, ethical or political position
2349     regarding them.
2350
2351     The "Invariant Sections" are certain Secondary Sections whose
2352     titles are designated, as being those of Invariant Sections, in
2353     the notice that says that the Document is released under this
2354     License.  If a section does not fit the above definition of
2355     Secondary then it is not allowed to be designated as Invariant.
2356     The Document may contain zero Invariant Sections.  If the Document
2357     does not identify any Invariant Sections then there are none.
2358
2359     The "Cover Texts" are certain short passages of text that are
2360     listed, as Front-Cover Texts or Back-Cover Texts, in the notice
2361     that says that the Document is released under this License.  A
2362     Front-Cover Text may be at most 5 words, and a Back-Cover Text may
2363     be at most 25 words.
2364
2365     A "Transparent" copy of the Document means a machine-readable copy,
2366     represented in a format whose specification is available to the
2367     general public, that is suitable for revising the document
2368     straightforwardly with generic text editors or (for images
2369     composed of pixels) generic paint programs or (for drawings) some
2370     widely available drawing editor, and that is suitable for input to
2371     text formatters or for automatic translation to a variety of
2372     formats suitable for input to text formatters.  A copy made in an
2373     otherwise Transparent file format whose markup, or absence of
2374     markup, has been arranged to thwart or discourage subsequent
2375     modification by readers is not Transparent.  An image format is
2376     not Transparent if used for any substantial amount of text.  A
2377     copy that is not "Transparent" is called "Opaque".
2378
2379     Examples of suitable formats for Transparent copies include plain
2380     ASCII without markup, Texinfo input format, LaTeX input format,
2381     SGML or XML using a publicly available DTD, and
2382     standard-conforming simple HTML, PostScript or PDF designed for
2383     human modification.  Examples of transparent image formats include
2384     PNG, XCF and JPG.  Opaque formats include proprietary formats that
2385     can be read and edited only by proprietary word processors, SGML or
2386     XML for which the DTD and/or processing tools are not generally
2387     available, and the machine-generated HTML, PostScript or PDF
2388     produced by some word processors for output purposes only.
2389
2390     The "Title Page" means, for a printed book, the title page itself,
2391     plus such following pages as are needed to hold, legibly, the
2392     material this License requires to appear in the title page.  For
2393     works in formats which do not have any title page as such, "Title
2394     Page" means the text near the most prominent appearance of the
2395     work's title, preceding the beginning of the body of the text.
2396
2397     The "publisher" means any person or entity that distributes copies
2398     of the Document to the public.
2399
2400     A section "Entitled XYZ" means a named subunit of the Document
2401     whose title either is precisely XYZ or contains XYZ in parentheses
2402     following text that translates XYZ in another language.  (Here XYZ
2403     stands for a specific section name mentioned below, such as
2404     "Acknowledgements", "Dedications", "Endorsements", or "History".)
2405     To "Preserve the Title" of such a section when you modify the
2406     Document means that it remains a section "Entitled XYZ" according
2407     to this definition.
2408
2409     The Document may include Warranty Disclaimers next to the notice
2410     which states that this License applies to the Document.  These
2411     Warranty Disclaimers are considered to be included by reference in
2412     this License, but only as regards disclaiming warranties: any other
2413     implication that these Warranty Disclaimers may have is void and
2414     has no effect on the meaning of this License.
2415
2416  2. VERBATIM COPYING
2417
2418     You may copy and distribute the Document in any medium, either
2419     commercially or noncommercially, provided that this License, the
2420     copyright notices, and the license notice saying this License
2421     applies to the Document are reproduced in all copies, and that you
2422     add no other conditions whatsoever to those of this License.  You
2423     may not use technical measures to obstruct or control the reading
2424     or further copying of the copies you make or distribute.  However,
2425     you may accept compensation in exchange for copies.  If you
2426     distribute a large enough number of copies you must also follow
2427     the conditions in section 3.
2428
2429     You may also lend copies, under the same conditions stated above,
2430     and you may publicly display copies.
2431
2432  3. COPYING IN QUANTITY
2433
2434     If you publish printed copies (or copies in media that commonly
2435     have printed covers) of the Document, numbering more than 100, and
2436     the Document's license notice requires Cover Texts, you must
2437     enclose the copies in covers that carry, clearly and legibly, all
2438     these Cover Texts: Front-Cover Texts on the front cover, and
2439     Back-Cover Texts on the back cover.  Both covers must also clearly
2440     and legibly identify you as the publisher of these copies.  The
2441     front cover must present the full title with all words of the
2442     title equally prominent and visible.  You may add other material
2443     on the covers in addition.  Copying with changes limited to the
2444     covers, as long as they preserve the title of the Document and
2445     satisfy these conditions, can be treated as verbatim copying in
2446     other respects.
2447
2448     If the required texts for either cover are too voluminous to fit
2449     legibly, you should put the first ones listed (as many as fit
2450     reasonably) on the actual cover, and continue the rest onto
2451     adjacent pages.
2452
2453     If you publish or distribute Opaque copies of the Document
2454     numbering more than 100, you must either include a
2455     machine-readable Transparent copy along with each Opaque copy, or
2456     state in or with each Opaque copy a computer-network location from
2457     which the general network-using public has access to download
2458     using public-standard network protocols a complete Transparent
2459     copy of the Document, free of added material.  If you use the
2460     latter option, you must take reasonably prudent steps, when you
2461     begin distribution of Opaque copies in quantity, to ensure that
2462     this Transparent copy will remain thus accessible at the stated
2463     location until at least one year after the last time you
2464     distribute an Opaque copy (directly or through your agents or
2465     retailers) of that edition to the public.
2466
2467     It is requested, but not required, that you contact the authors of
2468     the Document well before redistributing any large number of
2469     copies, to give them a chance to provide you with an updated
2470     version of the Document.
2471
2472  4. MODIFICATIONS
2473
2474     You may copy and distribute a Modified Version of the Document
2475     under the conditions of sections 2 and 3 above, provided that you
2476     release the Modified Version under precisely this License, with
2477     the Modified Version filling the role of the Document, thus
2478     licensing distribution and modification of the Modified Version to
2479     whoever possesses a copy of it.  In addition, you must do these
2480     things in the Modified Version:
2481
2482       A. Use in the Title Page (and on the covers, if any) a title
2483          distinct from that of the Document, and from those of
2484          previous versions (which should, if there were any, be listed
2485          in the History section of the Document).  You may use the
2486          same title as a previous version if the original publisher of
2487          that version gives permission.
2488
2489       B. List on the Title Page, as authors, one or more persons or
2490          entities responsible for authorship of the modifications in
2491          the Modified Version, together with at least five of the
2492          principal authors of the Document (all of its principal
2493          authors, if it has fewer than five), unless they release you
2494          from this requirement.
2495
2496       C. State on the Title page the name of the publisher of the
2497          Modified Version, as the publisher.
2498
2499       D. Preserve all the copyright notices of the Document.
2500
2501       E. Add an appropriate copyright notice for your modifications
2502          adjacent to the other copyright notices.
2503
2504       F. Include, immediately after the copyright notices, a license
2505          notice giving the public permission to use the Modified
2506          Version under the terms of this License, in the form shown in
2507          the Addendum below.
2508
2509       G. Preserve in that license notice the full lists of Invariant
2510          Sections and required Cover Texts given in the Document's
2511          license notice.
2512
2513       H. Include an unaltered copy of this License.
2514
2515       I. Preserve the section Entitled "History", Preserve its Title,
2516          and add to it an item stating at least the title, year, new
2517          authors, and publisher of the Modified Version as given on
2518          the Title Page.  If there is no section Entitled "History" in
2519          the Document, create one stating the title, year, authors,
2520          and publisher of the Document as given on its Title Page,
2521          then add an item describing the Modified Version as stated in
2522          the previous sentence.
2523
2524       J. Preserve the network location, if any, given in the Document
2525          for public access to a Transparent copy of the Document, and
2526          likewise the network locations given in the Document for
2527          previous versions it was based on.  These may be placed in
2528          the "History" section.  You may omit a network location for a
2529          work that was published at least four years before the
2530          Document itself, or if the original publisher of the version
2531          it refers to gives permission.
2532
2533       K. For any section Entitled "Acknowledgements" or "Dedications",
2534          Preserve the Title of the section, and preserve in the
2535          section all the substance and tone of each of the contributor
2536          acknowledgements and/or dedications given therein.
2537
2538       L. Preserve all the Invariant Sections of the Document,
2539          unaltered in their text and in their titles.  Section numbers
2540          or the equivalent are not considered part of the section
2541          titles.
2542
2543       M. Delete any section Entitled "Endorsements".  Such a section
2544          may not be included in the Modified Version.
2545
2546       N. Do not retitle any existing section to be Entitled
2547          "Endorsements" or to conflict in title with any Invariant
2548          Section.
2549
2550       O. Preserve any Warranty Disclaimers.
2551
2552     If the Modified Version includes new front-matter sections or
2553     appendices that qualify as Secondary Sections and contain no
2554     material copied from the Document, you may at your option
2555     designate some or all of these sections as invariant.  To do this,
2556     add their titles to the list of Invariant Sections in the Modified
2557     Version's license notice.  These titles must be distinct from any
2558     other section titles.
2559
2560     You may add a section Entitled "Endorsements", provided it contains
2561     nothing but endorsements of your Modified Version by various
2562     parties--for example, statements of peer review or that the text
2563     has been approved by an organization as the authoritative
2564     definition of a standard.
2565
2566     You may add a passage of up to five words as a Front-Cover Text,
2567     and a passage of up to 25 words as a Back-Cover Text, to the end
2568     of the list of Cover Texts in the Modified Version.  Only one
2569     passage of Front-Cover Text and one of Back-Cover Text may be
2570     added by (or through arrangements made by) any one entity.  If the
2571     Document already includes a cover text for the same cover,
2572     previously added by you or by arrangement made by the same entity
2573     you are acting on behalf of, you may not add another; but you may
2574     replace the old one, on explicit permission from the previous
2575     publisher that added the old one.
2576
2577     The author(s) and publisher(s) of the Document do not by this
2578     License give permission to use their names for publicity for or to
2579     assert or imply endorsement of any Modified Version.
2580
2581  5. COMBINING DOCUMENTS
2582
2583     You may combine the Document with other documents released under
2584     this License, under the terms defined in section 4 above for
2585     modified versions, provided that you include in the combination
2586     all of the Invariant Sections of all of the original documents,
2587     unmodified, and list them all as Invariant Sections of your
2588     combined work in its license notice, and that you preserve all
2589     their Warranty Disclaimers.
2590
2591     The combined work need only contain one copy of this License, and
2592     multiple identical Invariant Sections may be replaced with a single
2593     copy.  If there are multiple Invariant Sections with the same name
2594     but different contents, make the title of each such section unique
2595     by adding at the end of it, in parentheses, the name of the
2596     original author or publisher of that section if known, or else a
2597     unique number.  Make the same adjustment to the section titles in
2598     the list of Invariant Sections in the license notice of the
2599     combined work.
2600
2601     In the combination, you must combine any sections Entitled
2602     "History" in the various original documents, forming one section
2603     Entitled "History"; likewise combine any sections Entitled
2604     "Acknowledgements", and any sections Entitled "Dedications".  You
2605     must delete all sections Entitled "Endorsements."
2606
2607  6. COLLECTIONS OF DOCUMENTS
2608
2609     You may make a collection consisting of the Document and other
2610     documents released under this License, and replace the individual
2611     copies of this License in the various documents with a single copy
2612     that is included in the collection, provided that you follow the
2613     rules of this License for verbatim copying of each of the
2614     documents in all other respects.
2615
2616     You may extract a single document from such a collection, and
2617     distribute it individually under this License, provided you insert
2618     a copy of this License into the extracted document, and follow
2619     this License in all other respects regarding verbatim copying of
2620     that document.
2621
2622  7. AGGREGATION WITH INDEPENDENT WORKS
2623
2624     A compilation of the Document or its derivatives with other
2625     separate and independent documents or works, in or on a volume of
2626     a storage or distribution medium, is called an "aggregate" if the
2627     copyright resulting from the compilation is not used to limit the
2628     legal rights of the compilation's users beyond what the individual
2629     works permit.  When the Document is included in an aggregate, this
2630     License does not apply to the other works in the aggregate which
2631     are not themselves derivative works of the Document.
2632
2633     If the Cover Text requirement of section 3 is applicable to these
2634     copies of the Document, then if the Document is less than one half
2635     of the entire aggregate, the Document's Cover Texts may be placed
2636     on covers that bracket the Document within the aggregate, or the
2637     electronic equivalent of covers if the Document is in electronic
2638     form.  Otherwise they must appear on printed covers that bracket
2639     the whole aggregate.
2640
2641  8. TRANSLATION
2642
2643     Translation is considered a kind of modification, so you may
2644     distribute translations of the Document under the terms of section
2645     4.  Replacing Invariant Sections with translations requires special
2646     permission from their copyright holders, but you may include
2647     translations of some or all Invariant Sections in addition to the
2648     original versions of these Invariant Sections.  You may include a
2649     translation of this License, and all the license notices in the
2650     Document, and any Warranty Disclaimers, provided that you also
2651     include the original English version of this License and the
2652     original versions of those notices and disclaimers.  In case of a
2653     disagreement between the translation and the original version of
2654     this License or a notice or disclaimer, the original version will
2655     prevail.
2656
2657     If a section in the Document is Entitled "Acknowledgements",
2658     "Dedications", or "History", the requirement (section 4) to
2659     Preserve its Title (section 1) will typically require changing the
2660     actual title.
2661
2662  9. TERMINATION
2663
2664     You may not copy, modify, sublicense, or distribute the Document
2665     except as expressly provided under this License.  Any attempt
2666     otherwise to copy, modify, sublicense, or distribute it is void,
2667     and will automatically terminate your rights under this License.
2668
2669     However, if you cease all violation of this License, then your
2670     license from a particular copyright holder is reinstated (a)
2671     provisionally, unless and until the copyright holder explicitly
2672     and finally terminates your license, and (b) permanently, if the
2673     copyright holder fails to notify you of the violation by some
2674     reasonable means prior to 60 days after the cessation.
2675
2676     Moreover, your license from a particular copyright holder is
2677     reinstated permanently if the copyright holder notifies you of the
2678     violation by some reasonable means, this is the first time you have
2679     received notice of violation of this License (for any work) from
2680     that copyright holder, and you cure the violation prior to 30 days
2681     after your receipt of the notice.
2682
2683     Termination of your rights under this section does not terminate
2684     the licenses of parties who have received copies or rights from
2685     you under this License.  If your rights have been terminated and
2686     not permanently reinstated, receipt of a copy of some or all of
2687     the same material does not give you any rights to use it.
2688
2689 10. FUTURE REVISIONS OF THIS LICENSE
2690
2691     The Free Software Foundation may publish new, revised versions of
2692     the GNU Free Documentation License from time to time.  Such new
2693     versions will be similar in spirit to the present version, but may
2694     differ in detail to address new problems or concerns.  See
2695     `http://www.gnu.org/copyleft/'.
2696
2697     Each version of the License is given a distinguishing version
2698     number.  If the Document specifies that a particular numbered
2699     version of this License "or any later version" applies to it, you
2700     have the option of following the terms and conditions either of
2701     that specified version or of any later version that has been
2702     published (not as a draft) by the Free Software Foundation.  If
2703     the Document does not specify a version number of this License,
2704     you may choose any version ever published (not as a draft) by the
2705     Free Software Foundation.  If the Document specifies that a proxy
2706     can decide which future versions of this License can be used, that
2707     proxy's public statement of acceptance of a version permanently
2708     authorizes you to choose that version for the Document.
2709
2710 11. RELICENSING
2711
2712     "Massive Multiauthor Collaboration Site" (or "MMC Site") means any
2713     World Wide Web server that publishes copyrightable works and also
2714     provides prominent facilities for anybody to edit those works.  A
2715     public wiki that anybody can edit is an example of such a server.
2716     A "Massive Multiauthor Collaboration" (or "MMC") contained in the
2717     site means any set of copyrightable works thus published on the MMC
2718     site.
2719
2720     "CC-BY-SA" means the Creative Commons Attribution-Share Alike 3.0
2721     license published by Creative Commons Corporation, a not-for-profit
2722     corporation with a principal place of business in San Francisco,
2723     California, as well as future copyleft versions of that license
2724     published by that same organization.
2725
2726     "Incorporate" means to publish or republish a Document, in whole or
2727     in part, as part of another Document.
2728
2729     An MMC is "eligible for relicensing" if it is licensed under this
2730     License, and if all works that were first published under this
2731     License somewhere other than this MMC, and subsequently
2732     incorporated in whole or in part into the MMC, (1) had no cover
2733     texts or invariant sections, and (2) were thus incorporated prior
2734     to November 1, 2008.
2735
2736     The operator of an MMC Site may republish an MMC contained in the
2737     site under CC-BY-SA on the same site at any time before August 1,
2738     2009, provided the MMC is eligible for relicensing.
2739
2740
2741ADDENDUM: How to use this License for your documents
2742====================================================
2743
2744To use this License in a document you have written, include a copy of
2745the License in the document and put the following copyright and license
2746notices just after the title page:
2747
2748       Copyright (C)  YEAR  YOUR NAME.
2749       Permission is granted to copy, distribute and/or modify this document
2750       under the terms of the GNU Free Documentation License, Version 1.3
2751       or any later version published by the Free Software Foundation;
2752       with no Invariant Sections, no Front-Cover Texts, and no Back-Cover
2753       Texts.  A copy of the license is included in the section entitled ``GNU
2754       Free Documentation License''.
2755
2756   If you have Invariant Sections, Front-Cover Texts and Back-Cover
2757Texts, replace the "with...Texts." line with this:
2758
2759         with the Invariant Sections being LIST THEIR TITLES, with
2760         the Front-Cover Texts being LIST, and with the Back-Cover Texts
2761         being LIST.
2762
2763   If you have Invariant Sections without Cover Texts, or some other
2764combination of the three, merge those two alternatives to suit the
2765situation.
2766
2767   If your document contains nontrivial examples of program code, we
2768recommend releasing these examples in parallel under your choice of
2769free software license, such as the GNU General Public License, to
2770permit their use in free software.
2771
2772
2773File: libgomp.info,  Node: Funding,  Next: Library Index,  Prev: GNU Free Documentation License,  Up: Top
2774
2775Funding Free Software
2776*********************
2777
2778If you want to have more free software a few years from now, it makes
2779sense for you to help encourage people to contribute funds for its
2780development.  The most effective approach known is to encourage
2781commercial redistributors to donate.
2782
2783   Users of free software systems can boost the pace of development by
2784encouraging for-a-fee distributors to donate part of their selling price
2785to free software developers--the Free Software Foundation, and others.
2786
2787   The way to convince distributors to do this is to demand it and
2788expect it from them.  So when you compare distributors, judge them
2789partly by how much they give to free software development.  Show
2790distributors they must compete to be the one who gives the most.
2791
2792   To make this approach work, you must insist on numbers that you can
2793compare, such as, "We will donate ten dollars to the Frobnitz project
2794for each disk sold."  Don't be satisfied with a vague promise, such as
2795"A portion of the profits are donated," since it doesn't give a basis
2796for comparison.
2797
2798   Even a precise fraction "of the profits from this disk" is not very
2799meaningful, since creative accounting and unrelated business decisions
2800can greatly alter what fraction of the sales price counts as profit.
2801If the price you pay is $50, ten percent of the profit is probably less
2802than a dollar; it might be a few cents, or nothing at all.
2803
2804   Some redistributors do development work themselves.  This is useful
2805too; but to keep everyone honest, you need to inquire how much they do,
2806and what kind.  Some kinds of development make much more long-term
2807difference than others.  For example, maintaining a separate version of
2808a program contributes very little; maintaining the standard version of a
2809program for the whole community contributes much.  Easy new ports
2810contribute little, since someone else would surely do them; difficult
2811ports such as adding a new CPU to the GNU Compiler Collection
2812contribute more; major new features or packages contribute the most.
2813
2814   By establishing the idea that supporting further development is "the
2815proper thing to do" when distributing free software for a fee, we can
2816assure a steady flow of resources into making more free software.
2817
2818     Copyright (C) 1994 Free Software Foundation, Inc.
2819     Verbatim copying and redistribution of this section is permitted
2820     without royalty; alteration is not permitted.
2821
2822
2823File: libgomp.info,  Node: Library Index,  Prev: Funding,  Up: Top
2824
2825Library Index
2826*************
2827
2828[index]
2829* Menu:
2830
2831* Environment Variable <1>:              GOMP_STACKSIZE.        (line 6)
2832* Environment Variable <2>:              GOMP_CPU_AFFINITY.     (line 6)
2833* Environment Variable <3>:              OMP_PROC_BIND.         (line 6)
2834* Environment Variable <4>:              OMP_WAIT_POLICY.       (line 6)
2835* Environment Variable <5>:              OMP_THREAD_LIMIT.      (line 6)
2836* Environment Variable <6>:              OMP_STACKSIZE.         (line 6)
2837* Environment Variable <7>:              OMP_SCHEDULE.          (line 6)
2838* Environment Variable <8>:              OMP_NUM_THREADS.       (line 6)
2839* Environment Variable <9>:              OMP_NESTED.            (line 6)
2840* Environment Variable <10>:             OMP_MAX_ACTIVE_LEVELS. (line 6)
2841* Environment Variable:                  OMP_DYNAMIC.           (line 6)
2842* FDL, GNU Free Documentation License:   GNU Free Documentation License.
2843                                                                (line 6)
2844* Implementation specific setting <1>:   GOMP_STACKSIZE.        (line 6)
2845* Implementation specific setting <2>:   OMP_SCHEDULE.          (line 6)
2846* Implementation specific setting <3>:   OMP_NUM_THREADS.       (line 6)
2847* Implementation specific setting:       OMP_NESTED.            (line 6)
2848* Introduction:                          Top.                   (line 6)
2849
2850
2851
2852Tag Table:
2853Node: Top2039
2854Node: Enabling OpenMP3233
2855Node: Runtime Library Routines4018
2856Node: omp_get_active_level6466
2857Node: omp_get_ancestor_thread_num7170
2858Node: omp_get_dynamic8097
2859Node: omp_get_level8975
2860Node: omp_get_max_active_levels9599
2861Node: omp_get_max_threads10302
2862Node: omp_get_nested11058
2863Node: omp_get_num_procs11970
2864Node: omp_get_num_threads12488
2865Node: omp_get_schedule13570
2866Node: omp_get_team_size14491
2867Node: omp_get_thread_limit15453
2868Node: omp_get_thread_num16076
2869Node: omp_in_parallel16944
2870Node: omp_in_final17591
2871Node: omp_set_dynamic18262
2872Node: omp_set_max_active_levels19099
2873Node: omp_set_nested19879
2874Node: omp_set_num_threads20758
2875Node: omp_set_schedule21594
2876Node: omp_init_lock22666
2877Node: omp_set_lock23317
2878Node: omp_test_lock24168
2879Node: omp_unset_lock25139
2880Node: omp_destroy_lock26065
2881Node: omp_init_nest_lock26739
2882Node: omp_set_nest_lock27472
2883Node: omp_test_nest_lock28383
2884Node: omp_unset_nest_lock29412
2885Node: omp_destroy_nest_lock30422
2886Node: omp_get_wtick31170
2887Node: omp_get_wtime31761
2888Node: Environment Variables32535
2889Node: OMP_DYNAMIC33663
2890Node: OMP_MAX_ACTIVE_LEVELS34231
2891Node: OMP_NESTED34870
2892Node: OMP_NUM_THREADS35474
2893Node: OMP_SCHEDULE36162
2894Node: OMP_STACKSIZE36856
2895Node: OMP_THREAD_LIMIT37682
2896Node: OMP_WAIT_POLICY38277
2897Node: OMP_PROC_BIND38838
2898Node: GOMP_CPU_AFFINITY39396
2899Node: GOMP_STACKSIZE40937
2900Node: The libgomp ABI41747
2901Node: Implementing MASTER construct42546
2902Node: Implementing CRITICAL construct42960
2903Node: Implementing ATOMIC construct43699
2904Node: Implementing FLUSH construct44180
2905Node: Implementing BARRIER construct44451
2906Node: Implementing THREADPRIVATE construct44720
2907Node: Implementing PRIVATE clause45372
2908Node: Implementing FIRSTPRIVATE LASTPRIVATE COPYIN and COPYPRIVATE clauses45953
2909Node: Implementing REDUCTION clause47277
2910Node: Implementing PARALLEL construct47834
2911Node: Implementing FOR construct49091
2912Node: Implementing ORDERED construct51089
2913Node: Implementing SECTIONS construct51395
2914Node: Implementing SINGLE construct52161
2915Node: Reporting Bugs52823
2916Node: Copying53133
2917Node: GNU Free Documentation License90698
2918Node: Funding115840
2919Node: Library Index118365
2920
2921End Tag Table
2922